templatefilters: wrap all filters in dedicated functions
This will highly simplify the docstring integration. I measured "hg log
--style=changelog" duration on mercurial itself and could not detect any
difference.
#!/usr/bin/env python
import errno, os, sys
for f in sys.argv[1:]:
try:
print f, '->', os.readlink(f)
except OSError, err:
if err.errno != errno.EINVAL:
raise
print f, 'not a symlink'
sys.exit(0)