Recommend the right call instead of datetime.now()

Closes-Bug: #1258166
Change-Id: I92b94dbcd0405d8f2bb818ad1c44c4f4934c8bec
Workers verification for WSGI service

When we start the nova-api service, the *_workers (metadata_workers,
ec2_workers, osapi_compute_workers) value are not verified if the value
is negative. If the user passes a negative value accidentally, and
InvalidInput exception will be threw.

Change-Id: I8337d672cb119efe700aa6be420fdac9864c1577
Closes-bug: #1269997
Remove extra space in log message

Change-Id: I52993874dad7d89edcdaba36e1227c26cc3e8f43
Remove XML support from migrations pci multiple_create v3 API plugins

Remove XML support from the following v3 compute API plugins:

 - migrations
 - multiple_create
 - pci

Part of blueprint remove-v3-xml-api

DocImpact

Change-Id: If7dfda52eea63a39fae0e546cfeaf4b1d814b7b9
Merge "Remove extra space in log message"
Merge "Recommend the right call instead of datetime.now()"
Merge "Remove XML support from migrations pci multiple_create v3 API plugins"
Merge "Workers verification for WSGI service"