Update Carve to newest upstream version with some assorted fixes

Perhaps some warnings could be silenced, but not in mood of writing
local patches at this moment. They're all harmless anyway.

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@54846 954f8c5b-7b00-dc11-b283-0030488c597c