Harmonize quotes used
Move test concerning PackageListingAcl to the appropriate file
Fix distTag in the test
Add methods by_collectionid and a branch to PackageListing
Add the add_branch method to the API

Note: only Approved package are branched, not Orphaned, Deprecated or Removed
Add unit-tests corresponding to latest methods (branch, by_collectionid and add_branch)
Add tests checking the add_branch raises exceptions when it should
Catch SQLAlchemyError when branching ACLs, keep them and return them later
Improve documentation of the API
Add test for get_acl_package

Make sure it raises the correct exception if provided with the (in)correct data.
Remove a try/except that we cannot run into and don't cover SQL exception
Improve web API documentation and allow a more flexible routing (wrt trailing slash)
Adjust web API unit-test accordingly
Fix change of function name
Replace <> by quotes as rest seems to not like them
Revert "Replace <> by quotes as rest seems to not like them"

This reverts commit a74d13ca4d3f468bf14b2bb17b4e8bd355951d0a which apparently
was not the sources of the problem I was seeing
Use trailing slash to break up the first line over two lines
Add the pkgdb version information on the template of the API namespace as well
Expand documentation about the argument required for a new collection (web API)
Add import SESSION where it was missing in the API