fix bug that can't create collaborator more than one
add time zone system
support time zone
use hoedown for fenced code support
add changes
add parent.pm
upgrade module version
Renamed encoding to default_encoding

no functionality change. this is just code clean-up.
Supported multiple character encoding of source code

Added new config parameter 'encoding_suspects' to put suspects encoding list.
commit diff, normal blob and blame are converted by Encode::Guess with suspects encoding list.