Updated mediawiki/extensions
Project: mediawiki/extensions/timeline  5255e6253f51660c1e351b766db757914a9b4fd5

omit the .ttf extension in default font name

Per the Ploticus docs[1], font name shouldn't include the .ttf extension.
This seems to work for the PNG renderer, but causes issues with SVG files
(including the svg2png renderer).

Also clean up and extend docs for $wgTimelineSettings->fontFile.

[1] http://ploticus.sourceforge.net/doc/fonts.html

Change-Id: I03a7f99b98d78d8733ca5b93ab365a0b851d5485