fixing blank page for account messages page, making it redirect proper, deleting cruft messages page under profile
Close #706; update symfony2 components
Merge pull request #821 from evancooper/message_pages_issue

Fixing blank page for account messages page, making it redirect proper, ...
Guess in underscore conditional town, gotta make sure thing exists before you check if its greater than zero.
Merge branch 'parent_id_chicanery' of https://github.com/evancooper/concrete5-5.7.0 into evancooper-parent_id_chicanery
Fix #764
Fix #748