Exit w/ valid code when no servers are deleted.

This change updates do_delete in v1_1/shell.py to keep track of
deletion failures and raises an exception when all of the specified
servers cannot be deleted.  This in turn causes nova client to exit
with a correct exit code when no successful deletes occur.

Change-Id: I16ee7a4c754cf2e8add09a41becbcc37edc767ff
Fixes: bug #1185009
The 'nova keypair-show key_name' command added.

* 'os-keypairs' api extension used.

Change-Id: Idbb529135b6629f02306c49d8095b5fcf94770cc
Set default value of flavorid to "auto"

Fixes: Bug #1189877
Change-Id: I80a0834c5f1d264b64f14d78fa2f71b1e4d9d89a
Merge "Set default value of flavorid to "auto""
Merge "Exit w/ valid code when no servers are deleted."
Merge "The 'nova keypair-show key_name' command added."