Merge branch 'master' into releases3

Conflicts:
	.travis.yml
sort_by! is not supported on ruby 1.8
display only self-and-descendants projects issues in release backlog views, so one can focus by going down the project hierarchy
separate disabling of productbl from releases
releases sharing simplified: they can be made visible for parent projects, but can contain only stories from their own project
Revert "releases sharing simplified: they can be made visible for parent projects, but can contain only stories from their own project"

This reverts commit 06dbd4de1ca146d586ca5fea5bc461bef9f11458.
use correct selector for product backlog on DnD handling
full release sharing, drop-restrictions on sub-views
Merge branch 'master' into releases3

Conflicts:
	app/views/rb_server_variables/show.js.erb
do not drop old release table/colum for now
add release to history. No migration of old data
List shared releases when editing issue from RM.
Added basic test for journal and history tracking for releases.
Remove old release tests (never been running...)
Awesome release-feature and tons of other fixes deserves some credit.
v0.9.35
Added release to story tooltip
Merge remote branch 'origin/master' into releases3
Disabled release burndown graph for now
Merge pull request #799 from backlogs/releases3

Releases3 - planned releases