Merge ceilometer-collector and ceilometer-collector-udp

This will simplify deployment.

Change-Id: Iabf88eafae4e95825016d382cfa86ceb8c38f880
Move dispatcher a level up

Dispatcher as it is designed now is used by both collector and
agent-notification, so let's move it level upper. This makes a more flat
hierarchy.

Change-Id: I681bf58f0b26cca22a48e6655db2547e59f9e805
Remove the collector submodule

It's useless to have a submodule with just one service, simplify the
hierarchy.

Change-Id: I4c39ea74fc5cb59d487626b998eaed9c5cf30eff
Use map_method from stevedore 0.12

This simplifies the code a bit.

Change-Id: If8b95bf8cd8c240efde51aa8b268a26998042345
Simplify the dispatcher method prototype

`record_metering_data' is receiving a context that is never used in the
dispatch drivers. So let's remove it to simplify our code and
interfaces.

Change-Id: I811fe86b86749de4c4d52a57e761021604f7b818
Avoid intermittent integrity error on alarm creation

Fixes bug 1255107

Previously, alarm creation failed intermittently with the
sqlalchemy driver, due to the reliance on session merge to create
the project & user IDs if not already encountered.  This approach
conflicted with the strict foreign key constraints that were
added to the alarms table as an after-thought.

Now, we avoid the potential problem by explicitly creating the
project and user IDs if necessary.

Unfortunately, this cannot be tested via the scenario tests,
as there we use sqlite (the problematic migration does not
apply the foreign key constraints for that engine).

Change-Id: Ieaed676a0a68725242fadbf658646b874d6851ce
Fixed nova notifier test

Fixed nova notifier test due to the nova change
https://review.openstack.org/54493.

Change-Id: Ia3b81eb63f642668185474b2a5a15d3fc0d87b1c
Closes-Bug: 1255409
Fixed a bug in sql migration script 020

In sql migration script 020_add_metadata_tables.py, the sql statements
to insert metadata from the meter table to the newly created tables
have never been executed.

Change-Id: I211e024ed8be65a19f670ce72e3035c8f8797a54
Merge "Merge ceilometer-collector and ceilometer-collector-udp"
Merge "Move dispatcher a level up"
Merge "Remove the collector submodule"
Merge "Use map_method from stevedore 0.12"
connection is not close in migration script

close the connection in migration script 021.
also close connection earlier.

Closes-Bug: #1255173
Change-Id: I27dab9bb08a5f9038d6a5fc1267c5a749b703a61
Merge "Fixed a bug in sql migration script 020"
Merge "connection is not close in migration script"
Merge "Avoid intermittent integrity error on alarm creation"
Merge "Simplify the dispatcher method prototype"