update forgotten Gemfile.lock
replace the rendering of planning elements with rabl

added oj and multijson, as they are supposedly faster as oj is
supposedly faster than the default-engine: There are still lots of
switches in rabl left to improve the speed even more.

Currently, only the inde-templates have been replaced, other templates
have been left untouched: The tests now break, as there is a special
test for the replaced .rsb-file: This is a very specialised test, we
should probably replace this with tests for an expected json-response.
Added a spec for the json-response of the api
fixing the xml-spec for planning-elements
added created at and updated_at
resolving merge-issues in Gemfile.lock
missing changelog-entries added
Merge pull request #509 from opf/feature/migrate_to_rabl
[opf #1854] fixed breadcrumb in chrome
whitespace fix in application.css
Merge pull request #510 from opf/feature/fix_breadcrumb

[opf #1854] fixed breadcrumb in chrome
added changelog entry for #1854
simple refactoring for the reports: maybe this gets it below D
major refactoring of reports into separare classes

reports now live in separate classes: This brought up several issues
with buggy templates; lots of duplicate code has now been removed.

Still needs some view-testing, and maybe some unit-testing for the
service.
Worked in the review-remarks, added proper coypright notices where missing
abstract-class is ActiveRecord only, removing it.
added changelog-entry
limits principals returned by the autocompleter to only active or registerd
cleaning up unused code, rewriting scopes
updates changelog