allow loading of pes by id.
validate access. specs.
Merge remote-tracking branch 'origin/feature/rails3' into fix/vertical_pe_loading

Conflicts:
	app/controllers/api/v2/planning_elements_controller.rb
uses appropriate work_packages proxy on repository
fixes image paths
fixes route globbing for repositories
removes outdated routes for repositories
adapts repository tests to changed routes
updates changelog
revert wrong change.
Merge pull request #524 from opf/fix/repository_bugs
refactor gets into before.
set new version
Merge pull request #541 from opf/fix/vertical_pe_loading
add changelog entry

[skip ci]
use \A and \z instead of ^ and $ in ruby regexes
Merge pull request #552 from opf/feature/rails3_repair_regexes

[WIP] use \A and \z instead of ^ and $ in ruby regexes
correctly validate svn urls
Restores project type and associations in timelines.
Fixes an API bug in association compisition.

Previously, only the project_b_id would be considered other.