Merge upstream branch and some changes for better readability

5 files changed, 24 insertions, 21 deletions

diff --git a/user_guide_src/source/libraries/config.rst b/user_guide_src/source/libraries/config.rst
index c81cad7b3..08d9c2905 100644
--- a/user_guide_src/source/libraries/config.rst
+++ b/user_guide_src/source/libraries/config.rst
@@ -149,11 +149,13 @@ folders:
 -  Your own custom configuration files
 
 .. note::
-	CodeIgniter always tries to load the configuration files for
-	the current environment first. If the file does not exist, the global
-	config file (i.e., the one in application/config/) is loaded. This means
-	you are not obligated to place **all** of your configuration files in an
-	environment folder − only the files that change per environment.
+	CodeIgniter always loads the global config file first (i.e., the one in application/config/),
+	then tries to load the configuration files for the current environment.
+	This means you are not obligated to place **all** of your configuration files in an
+	environment folder. Only the files that change per environment. Additionally you don't
+	have to copy **all** the config items in the environment config file. Only the config items
+	that you wish to change for your environment. The config items declared in your environment
+	folders always overwrite those in your global config files.
 
 Helper Functions
 ================
diff --git a/user_guide_src/source/libraries/email.rst b/user_guide_src/source/libraries/email.rst
index daf000907..f99eb91df 100644
--- a/user_guide_src/source/libraries/email.rst
+++ b/user_guide_src/source/libraries/email.rst
@@ -182,6 +182,14 @@ formatting which is added to the header string for people who do not
 accept HTML email. If you do not set your own message CodeIgniter will
 extract the message from your HTML email and strip the tags.
 
+$this->email->set_header()
+-----------------------
+
+Appends additional headers to the e-mail::
+
+	$this->email->set_header('Header1', 'Value1');
+	$this->email->set_header('Header2', 'Value2');
+
 $this->email->clear()
 ---------------------
 
diff --git a/user_guide_src/source/libraries/input.rst b/user_guide_src/source/libraries/input.rst
index 1f2ea650a..432bac3c7 100644
--- a/user_guide_src/source/libraries/input.rst
+++ b/user_guide_src/source/libraries/input.rst
@@ -18,7 +18,7 @@ The security filtering function is called automatically when a new
 :doc:`controller <../general/controllers>` is invoked. It does the
 following:
 
--  If $config['allow_get_array'] is FALSE(default is TRUE), destroys
+-  If $config['allow_get_array'] is FALSE (default is TRUE), destroys
    the global GET array.
 -  Destroys all global variables in the event register_globals is
    turned on.
@@ -53,14 +53,7 @@ false (boolean) if not. This lets you conveniently use data without
 having to test whether an item exists first. In other words, normally
 you might do something like this::
 
-	if ( ! isset($_POST['something']))
-	{
-	    $something = FALSE;
-	}
-	else
-	{
-	    $something = $_POST['something'];
-	}
+	$something = isset($_POST['something']) ? $_POST['something'] : NULL;
 
 With CodeIgniter's built in functions you can simply do this::
 
@@ -95,7 +88,7 @@ To return an array of all POST items call without any parameters.
 To return all POST items and pass them through the XSS filter set the
 first parameter NULL while setting the second parameter to boolean;
 
-The function returns FALSE (boolean) if there are no items in the POST.
+The function returns NULL if there are no items in the POST.
 
 ::
 
@@ -115,7 +108,7 @@ To return an array of all GET items call without any parameters.
 To return all GET items and pass them through the XSS filter set the
 first parameter NULL while setting the second parameter to boolean;
 
-The function returns FALSE (boolean) if there are no items in the GET.
+The function returns NULL if there are no items in the GET.
 
 ::
 
@@ -210,7 +203,7 @@ the cookie you are looking for (including any prefixes)::
 
 	cookie('some_cookie');
 
-The function returns FALSE (boolean) if the item you are attempting to
+The function returns NULL if the item you are attempting to
 retrieve does not exist.
 
 The second optional parameter lets you run the data through the XSS
diff --git a/user_guide_src/source/libraries/loader.rst b/user_guide_src/source/libraries/loader.rst
index 2090404bf..aadf9740a 100644
--- a/user_guide_src/source/libraries/loader.rst
+++ b/user_guide_src/source/libraries/loader.rst
@@ -116,12 +116,12 @@ assign it to a variable if you want the data returned::
 
 	$string = $this->load->view('myfile', '', true);
 
-$this->load->model('Model_name');
+$this->load->model('model_name');
 ==================================
 
 ::
 
-	$this->load->model('Model_name');
+	$this->load->model('model_name');
 
 
 If your model is located in a sub-folder, include the relative path from
@@ -134,7 +134,7 @@ application/models/blog/queries.php you'll load it using::
 If you would like your model assigned to a different object name you can
 specify it via the second parameter of the loading function::
 
-	$this->load->model('Model_name', 'fubar');
+	$this->load->model('model_name', 'fubar');
 
 	$this->fubar->function();
 
diff --git a/user_guide_src/source/libraries/uri.rst b/user_guide_src/source/libraries/uri.rst
index ee60b77d7..cdd76e322 100644
--- a/user_guide_src/source/libraries/uri.rst
+++ b/user_guide_src/source/libraries/uri.rst
@@ -25,7 +25,7 @@ The segment numbers would be this:
 #. metro
 #. crime_is_up
 
-By default the function returns FALSE (boolean) if the segment does not
+By default the function returns NULL if the segment does not
 exist. There is an optional second parameter that permits you to set
 your own default value if the segment is missing. For example, this
 would tell the function to return the number zero in the event of