Remove obsolete note from ldap

There was a note in the ldap assignment backend about normalizing
a DN using .upper(). This note is obsolete with the recent change
to use a DN compare function.

Change-Id: I34c69573498b5f2d2103ea485160df421c6f2b03
Related-Bug: #1309228
Code which gets and deletes elements of tree was moved to one method

Code which uses 'search_s' and 'delete_s' in ldap backends was moved
to a new method to remove duplication of code.

Added handling of exception ldap.NO_SUCH_OBJECT when we couldn't
find a search base while deleting. Now this exception is
not ignored. Instead of this raised NotFound exception
or more suitable (RoleNotFound, etc).

Also added handling of situation when we trying to delete
nonexisting entries.

Closes-Bug: #1316128
Change-Id: I8e7402337ab4d75ce8920e8158a6e1dd1ed97abd
document keystone-specs instead of LP blueprints in README

Change-Id: I1d6c97e5f6033c530baa8bb3e24c911f4b57a824
Compressed Token Provider

Blueprint: compress-tokens

Change-Id: I94d1eba74ca5901e6c6c08a7a7260b39c9037500
Add v2 & v3 API documentation

Keystone itself didn't have much documentation on the APIs it was
implementing, so I made space for that documentation first, and then
followed it with a first pass on what it takes to move things to v3.

Change-Id: I71ee6d3c87b6919eb2f7569069d91f3a00d6337c
bp: document-v2-to-v3-transition
Merge "Compressed Token Provider"
Merge "Add v2 & v3 API documentation"
Merge "document keystone-specs instead of LP blueprints in README"
Merge "Code which gets and deletes elements of tree was moved to one method"
Merge "Remove obsolete note from ldap"