Remove unused nova.crypto.compute_md5()

Remove nova.crypto.compute_md5() as it is:
 * unused
  * last user removed 3 years ago with commit bab3060
 * untested
 * incorrectly documented
  * return type is not a tuple, but a string
 * redundant
  * copied from boto which is a nova requirement
 * burdened with license text more verbose than associated code

Change-Id: Ia033d3359098fc0af8de00248dc14b4fe280e844
Remove logging in libvirt _connect_auth_cb to avoid eventlet locking

The _connect_auth_cb callback is logging a warning if credentials are
passed to the method from libvirt when connecting, but the comment right
above where the connection method is called on libvirt, it says don't do
any logging in that function because it can cause issues with how
eventlet does logging.

This has probably never been an issue because libvirt hasn't passed
credentials back to the callback, but if it did at some point we could
have a nasty locking problem so let's clean it up now.

See commit e4b0d8e9 for some related history.

The nested method is moved up a level so it can be tested directly.

Change-Id: Ie47aabbf81c5aeda9e12e1c9acc11f6c70c4bea7
Add Nova API Sample file & test for get keypair

This patch adds the new API Sample file and its test for Nova V2 and V3
get keypair APIs.

This patch extend the timstamps reg exp to allow the combination
of TZ and microsecond/

Closes-Bug: 1298769
Closes-Bug: 1298818

Change-Id: If695a23cf95862b7bec6fbc5bdf7fc1733d08d4a
Merge "Remove unused nova.crypto.compute_md5()"
Merge "Add Nova API Sample file & test for get keypair"
Merge "Remove logging in libvirt _connect_auth_cb to avoid eventlet locking"