templates/map-rss

fixes for gpg.py extension

- add copyright and license
- add i18n
- add 'sigs' command behaving like 'hg tags'
- change 'role' to 'comment' and output it only if there is one
- refactoring

default = "changelog"
header = header-rss.tmpl
changelog = changelog-rss.tmpl
changelogentry = changelogentry-rss.tmpl
filelog = filelog-rss.tmpl
filelogentry = filelogentry-rss.tmpl