Provide service type management code structure

Reasons for refactoring:
- current code structure is orientied on mysql management implementation;
- there is no chanse to make new service types management
code fittable in current package/module structure;
- backuping process implementation is mysql/percona-orientied,
it should be renamed and should be configurable due to service type;
- "query" is abstract word for querying into database,
current query.py implementation is SQL orientied - it should be renamed;

Updates:
1.Providing new package hierarchy:
   guestagent/manager/service_type/service.py
   guestagent/manager/service_type/manager.py
   guestagent/manager/service_type/system.py
2.Renaming strategy implementations per each service_type
   guestagent/strategies/backup/mysql_impl.py
3.Externalizing operating system definer form system.py
 which used in pkg.py
4.Renaming query to sql_query.

Implement: blueprint refactor-ga-for-other-engines-support
Change-Id: I5fa5f037056bedf5464e99720cbe03b877c27fba
Simulates events so run_tests.py executes 10x faster

This restores some functionality that had been removed earlier to use
a class from Oslo. It turns out making it work with the new Oslo RPC
manager code wasn't too hard, plus the new version is hopefully easier
to follow.

Change-Id: I18e4d06359f28605cd764a10ace791997f534ed7
Implements: blueprint bring-back-event-simulator
Fix service_type in instance creation using heat services

parameters supplied to heat template should use service_type instead of hard-coded mysql

Fixes: Bug 1241655

Change-Id: I3cce6b35fc40f4ff4cc45b04714067956fb1869c
Add tests for hosts mgmt commands

* moving the tests from trove-integration for host command

Implements: Blueprint host-mgmt-tests

Change-Id: I947ae348ebd0ff83625476f0b28180db8f50afdb
Fix white_box mode for integration tests.

* Removing outdated logic and old test paths that are
  hit when running instances tests in white_box mode.

Fixes: Bug #1243793
Change-Id: I944b63b9cf9ca0f5d8d2139cb2974f4c804ca30a
Merge "Provide service type management code structure"
Merge "Add tests for hosts mgmt commands"
Merge "Simulates events so run_tests.py executes 10x faster"
Merge "Fix white_box mode for integration tests."
Merge "Fix service_type in instance creation using heat services"