This commit extends limit of ID and objects to 64 (it means 63 meaning
characters and 1 for zero-terminator). CustomData layers names are also
extended.
Changed DNA structures and all places where length constants were hardcoded.
All names which are "generating" from ID block should be limited by MAX_ID_NAME-2,
all non-id names now has got own define called MAX_NAME which should be used all
over for non-id names to make further name migration stuff easier.
All name fields in DNA now have comment with constant which corresponds to
hardcoded numeric value which should make it easier to further update this
limits or even switch to non-hardcoded values in DNA.
Special thanks to Campbell who helped figuring out some issues and helped a lot
in finding all cases where hardcoded valued were still used in code.
Both of forwards and backwards compatibility is stored with blender versions newer
than January 5, 2011. Older versions had issue with placing null-terminator to
DNA strings on file load which will lead to some unpredictable behavior or even
crashes.
