enable coveralls support
Move simplify_filename from tag.c
Move functions from window.c
Move fix_fname from buffer.c
Move after_pathsep from misc2.c
Move same_directory from misc2.c
Move pathcmp from misc2.c
Move mch_expandpath from os_unix.c
Move shorten_fname{,1,s} and shorten_filenames from fileio.c
Move expand_wildcards{,_eval} from misc1.c
Move match_suffix from misc1.c
Move shorten_filenames back to fileio.c
Make FPC_* defines an enum type in path.h.
Add os_stat to os/fs module.
Refactor fullpathcmp.
Add unit tests for gettail.
Refactor gettail.
Move gettail_dir more closely to its usage.
Add unit tests for gettail_sep.
Refactor gettail_sep.