Don't use g_source_remove for signal handlers

This fixes reliable crashes when changing bookmarks or the read later
list if any single window has been closed.
Version 3.11.91
Version 3.12.0
doap: update URLs
Fixed Russian translation
Updated Indonesian translation
yelp: check if running on X11 before running gdk_x11_* code

https://bugzilla.gnome.org/show_bug.cgi?id=708181
Updated Swedish translation
yelp-window: Improvements to buttons and search bar
Removed read later
yelp-help-list: Fix double unref
Fix reference to old, unused struct member
yelp-window: Added "All Help" menu item
Merge branch 'master' into new-aday-design

Conflicts:
	src/yelp-window.c
Move some actions to the app menu
yelp-window: Use placeholder text on empty bookmarks list
yelp-window: Added back Ctrl+L, better key press handling for search
yelp-window: Don't show find bar when search bar is shown
yelp-settings: Port color code to GtkStyle