Revert "No need to signal the shader the AMD_vertex_shader_layer is enabled"

This reverts commit 2e0bec57570c27a37630e98a721a79127ea6e7f5.
Do not undefine builtin macros.
Fixed crash in debug mode when command line option -N is used.
Allow command line options --kart and --track to select locked tracks.
This will allow reviewers to post screenshot of new tracks.
two redundant lines of code that may have caused a tiny memory leak
Merge pull request #1833 from smalltock/smallRedundancy00

two redundant lines of code that may have caused a tiny memory leak
Disable texture compression on Intel Mesa too
Make some strings translatable
Add emit map to object pass 2 shader
Merge branch 'master' of https://github.com/supertuxkart/stk-code
Detect mesa version.
Removed unnecessary c_str().
Fix crash when track is not found.
Some string fixes.
Fixed a typo.
Fixed crash in creating user screen, which occured after rename player.

It's a bit quick and lazy fix. Probably other variables should be cleared too.
Remove unecessary files.
Fix memory leak found by vlj
Fix build
Removed ngettext, because tinygettext can't handle it.