Merge remote branch 'bss03/master'

• [DH] gfcombinefs.c

Avoid mixed-signedness comparision.

Since offset is non-negative, the cast will not lose data and we avoid compiler errors/warnings.

• [DH] gfcombinefs.c

Bail if offset is invalid.

Otherwise, mixed-signedness comparison below might change the sign of offset as part of the usual arithmetic conversions.

• [DH] gfcombinefs.c

gfc_setxattr: malloc can fail, cope with that

• [DH] gfcombinefs.c

Add a README

• [DH] README

Initial commit

• [DH] .gitignore
• [DH] Makefile
• [DH] gfcombinefs.c