avoid pass NULL to memcpy
avoid garbage assignment
dump_gdef() failed to loop over subfonts

Might crash when there are subfonts. Some typo here.
remove a premature free on fea_GDefLigCarets()
break on invalid glyphname in fea_parseCursiveSequence()
Initial a variable in fea_ParseGlyphClass()
Initialize line wrap count in dump_fpst_everythingelse()
init another variable in fea_ParseGlyphClass()
Merge pull request #1338 from mozbugbox/scan-build-featurefile

Fixes several potential bugs and coding errors.