Fix blenderplayer compilation (tm)
cleanup: disallow NULL arg to uvedit_aspect

also some typo's
Fix T42882: Now warn user when trying to append/link from older blender files.

Since we do not make any conversion in this case, worth warning user about
potential issues!
Amend to previous 'append warning' commit.

Actually, append/link *is* converted/updated, issue here is IPO-to-FCurves
code is not called from our do_version code, but later, directly from BKE_blender's
setup_app_data. This is bad but not easily fixed it seems, so for now
keep a warning in this case.

thanks Sergey for the headup.
Merge branch 'master' into value_ladder