Update postgresql-server-dev requirement to current debian stable
Add http urls for libxml in case ftp isn't available
check if a proposal title is a valid variant name

This is important because proposals may create variants with
the same name later on
Merge pull request #668 from xi/feature-fix-proposal-name-validation

check if a proposal title is a valid variant name
rm autofocus from proposal index
fix sectionpage url

This was broken for sectionpages which were not on the top level
fix make a string translatable
create message_button css
add message_button to debug/components
create message button component
move instance massmessage out of instance settings
remove massmessage from settings menu
add instance message button
rm message_button icon
Revert "Hide the byline in hierarchical page listings if children"

This reverts commit 153ae5ccaeef362854e9df58d6efd244b46511b4.

Conflicts:
	src/adhocracy/templates/page/tiles.html
recursive metadata for sectionpages
more prominent user message button
Fix database based static page creation / editing

Fixup 89900f1e88fc70ec70f95d7619cba1657bb9258c which accidently broke
database based static page creation / editing by making URLs coherently
(no trailing slash). This now fixes the corresponding controllers.
use Page.sectionpage_root() in comment helper
rm unneeded imports