strings marked as _("translate me")
2) Added _() for all names and descriptions for the tracks and GPs
3) Improved update_pot.sh to create the entries for all track and
GP files.
4) Updated supertuxkart.pot to include all GPs and tracks.
git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/trunk/supertuxkart@1844 178a84e3-b1eb-0310-8ba1-8eac791a3b58