Add documentation for pipeline configuration

Extend the configuration section of the development documentation
of Ceilometer to contain the configuration options of pipelines.

Change-Id: Ie033431716b32a41040d5b4738e6ba150c2c9da8
Closes-Bug: #1272988
Fix string-to-boolean casting in queries

There is a function that converts strings to boolean that uses the
following rule:
Strings-True ('1', 't', 'true', 'on', 'y', 'yes') are converted to True
Strings-False ('0', 'f', 'false', 'off', 'n', 'no') are converted to False

But there is a default value (False by default) that returned in case when
the string is not in any of lists above. So by default any string that is
not in Strings-True will be converted to False. We may change this behaviour
by using strict=True checking.

If user creates a query we should validate that only valid strings (as above)
or boolean True or False are used in case of boolean filter.

Relates to bug 1236496

Change-Id: I83a54f09d715269c2d356bb7979a0372e6f7d2d0
sync oslo common code

sync code with commit-id: 5e5a51b3ddc25b3242e8f4f4b5e5357942618662

Change-Id: If62f3bba14cdc74c78685b2fdf5aa769c4158a50
Move ceilometer-send-counter to a console script

Change-Id: I504f999a04da0e58da5e60201325e062e1c7d9c5
Blueprint: remove-counter
Updated from global requirements

Change-Id: Iec06d578879ff880152a1fa48d952a691a1b3306
Merge "Add documentation for pipeline configuration"
Merge "Move ceilometer-send-counter to a console script"
Merge "Fix string-to-boolean casting in queries"
Merge "Updated from global requirements"
Merge "sync oslo common code"
Handle Heat notifications stack CRUD

Add samples for all successfully CRUD operations :
- stack.create
- stack.delete
- stack.update
- stack.suspend
- stack.resume

Change-Id: I98ffd1544d184237dc91aed98b1ad7b2fce8734a