allow to set datetime format in format_date and format_time

This is especially usefull with the generic formats 'long',
'medium' and 'short'
use date_tag instaed of building time tag manually
use analog headings to overview
separate sections by hr
rm css rules
mv top_actions to utility
add "create new proposal" morelink in header
fixup df5a210

restore a heading I accidently subsituted before.
This fixes the publixphere theme
Merge pull request #634 from xi/feature-refactor-milestone-ui

refactor milestone ui