Bug 1380531 - Write initial CircleCI configuration for BMO

This is the first (working) iteration of a configuration that allows
CircleCI to build 'bmo' docker images that are runnable.

Some other changes were required for this:

1. The base image used in Dockerfile was changed from centos:6.7 to
   mozillabteam/bmo-base:slim.
   This is a new version of (github) mozilla-bteam/docker-bmo-base
   which is much smaller, and includes all the system RPMs and other
   bits that our bmo Dockerfile expects.
2. init.pl mistakenly had '--no-assets' which is not currently a checksetup.pl
   option.
3. 901-secure-mail-loop.t (which checks for an infinite loop) had
   to have its timeout increased because CircleCI sometimes is quite slow.
4. version.txt // __version__ now includes build information from CircleCI
   environmental variables

1 files changed, 9 insertions, 4 deletions

diff --git a/Bugzilla/Install/Localconfig.pm b/Bugzilla/Install/Localconfig.pm
index 4fb15a1c2..8807a44dd 100644
--- a/Bugzilla/Install/Localconfig.pm
+++ b/Bugzilla/Install/Localconfig.pm
@@ -44,11 +44,16 @@ sub _sensible_group {
 }
 
 sub _migrate_param {
-  my ($name, $fallback_value) = @_;
+    my ( $name, $fallback_value ) = @_;
 
-  return sub {
-      return Bugzilla->params->{$name} // $fallback_value;
-  };
+    return sub {
+        if ( Bugzilla->can('params') ) {
+            return Bugzilla->params->{$name} // $fallback_value;
+        }
+        else {
+            return $fallback_value;
+        }
+    };
 }
 
 use constant LOCALCONFIG_VARS => (