(bug 33454) Add format characters for timezone

The {{#timel:}} parser function lacks any way to output the timezone
used, and generates incorrect output for the 'c', 'r', and 'U'
formatting characters. This uses the timezone support added to core
Language::sprintfDate in Iea1f7842 to fix that.

Bug: 33454
Change-Id: I71f594132ce48140a95bd85e16183c4a1162ebef