Fix parameter checking about quota update api

In quota_classes and quotas update API, parameters are checked
whether they are integer or not.
But when pass float values to these APIs, error doesn't occur.
Float values should be forbidden for the following reasons.
(1)If the value that user submitted and the value registered
   actually are different, user will be confused.
(2)Error messages of these APIs are "...must be integer...".
(3)In horizon, if a float is submitted, error message is displayed.

This patch fixes this problem.

Change-Id: I4c7df52ffff2d997da4e6267e25ec2ea4ab6f153
Closes-Bug: #1243037
Merge "Fix parameter checking about quota update api"
XenAPI: get_info was very expensive

Getting the whole VM record is expensive and slowed down Tempest tests
significantly.  Replaced with getting each required item.

When getting power state, only need that specific value, so reduce the
calls to get_info too.

Change-Id: I93bcef5b692a531aac41518dc29d5d4f46cded65
XenAPI: Tidy calls to get_all_ref_and_rec

get_all_records is more efficient than getting them individually in the
old get_all_ref_and_rec implementation.

Replaced some cases of get_all_records with a faster and more
specific API call.

Change-Id: I4725c3f1fdebdf1737941cb7db69b19afb22df9f
XenAPI: Speedup get_vhd_parent_uuid

In many cases the VDI record has already been retrieved.
Use it rather than expensively getting a new VDI record from XAPI.

Change-Id: I469e2a415c1f1924010f47d3927ca18c45a7b8f8
XenAPI: Use get_VALUE in preference to get_record()['VALUE']

Replaces calls to get_record where only a single item is retrieved
from the record with the specific get_VALUE call.

Change-Id: I52e20c4f4c9d6a6ad019694916ee057cc96b18a6
XenAPI: Monitor the GC when coalescing

Add a new host plugin to monitor whether the garbage collector is running.
This is then used by the wait_for_vhd_coalesce function to know whether
waiting any more is likely to produce the expected results.

Increased the number of times we loop waiting for coalesce as the loop
now has knowledge that something is still happening.

Change-Id: Idcc0738945bd1aee8cdb52c9cfabd798f85c31db
Closes-bug: 1258169

Conflicts:

	nova/virt/xenapi/vm_utils.py
XenAPI: Use direct IO for writing config drive

If you don't use direct IO when writing to the device, the unplug
immediately following this may not succeed as the device may still
be in use.

Also add a sync to ensure the device is not being used at the point
of unplug.

Closes-bug: 1259163

Change-Id: I68f09835648b36772a7839af9718123a4c60734f