Exlde gstreamer when building XPIs
Allow overide on MOZ_APP_MAXVERSION

Adds option --soft-max-version.  This allows a 'soft' version number thus an
Aurora XPI of 24.0a2 will have an maximum compatible version of 24.0.* instead
of 24.0a2. This should allow someone to download an Aurora language pack and
use it in the final release.

Fix bug 3047
Cleanups: Add comments to ease code understanding
Typo
Docs: Expand non-conformance notes for PHP format
Docs: Replace formats supported section with link to PHP format docs
Fix: Reset prename when exiting the array

Perhaps several (not nested) arrays are declared in the same file, or
perhaps the file has mixed dialects for setting the localization strings.
Cleanups
Docs: Add more non-conformance cases for PHP format
Remove dead code in po2tmx.py
Docs: Fix example on styleguide
Cleanups: Remove unnecessary example on styleguide
Cleanups: Use code-block for styleguide examples
Cleanup: Remove code for supporting Python versions older than 2.5

There is still some code in the codebase that provides substitutes for code
present on newer Python versions, but those cleanups are left for the future.
Drop support for Python 2.5

There is still some code in the codebase that provides substitutes for code
present on newer Python versions, but those cleanups are left for the future.
Styleguide: Alter one-line docstring summary recommendations to match PEP 257
Cleanups: convert to sections
Docs: Add import order on styleguide
Docs: Add notes on from ... imports order and long imports in styleguide
Docs: Add section on properties to styleguide