Expand node-group-template usage validation msg

Now that we have a CLI, the error messages returned from validation
are presented directly to the user. Currently, node group templates
cannot be deleted if they are in use. This change expands the error
message to tell the user where the node group templates are in use.

Change-Id: I3764aa6730db52f2a313626054c941eb3a9723bc
Added EDP test for HDP plugin

Change-Id: I3dde5063ace374ca9c0e69866db23f9970aa605b
Added IDH plugin to savanna config

Implements blueprint idh-savanna-plugin

Change-Id: Ida02be6bb627d43e196106edf239522240c7eadf
[IDH] Removed copy-pasted test utility file

It seems that code was copied to IDH plugin before extracting test
utils from vanilla plugin to common code. Replaced copy-past with
usage of common code.

Change-Id: I452cc7f274a54f6e5e4972556d2cfc129069871e
Changed get_node_groups to receive only one node process

Ability to receive either string or list of strings makes code
hard to understand. Noone uses feature with list. So, removed it.

Closes-Bug: #1284402
Change-Id: I0d02321dc076f81769562378eb5e483dbc6c5565
Merge "Added EDP test for HDP plugin"
Updated from global requirements

Change-Id: I631705a6911f34197e9c99c81aa0025d3b9ef02c
Fix scale down cluster

Fixes bug: #1285533

Change-Id: Ib0d144ce81dac8ced7d334aa496a49e0f4837504
Merge "Added IDH plugin to savanna config"
Merge "[IDH] Removed copy-pasted test utility file"
[IDH] Added ability to support several versions

Implements: blueprint idh-several-versions

Change-Id: I0dcba11710739a60a38ba19b887eb2e63f2dc4d2
Merge "[IDH] Added ability to support several versions"
Merge "Changed get_node_groups to receive only one node process"
Merge "Fix scale down cluster"
Removed EDP dependency on job_tracker instance

Since we require oozie_server anyway we can communicate with
HDFS through it without involving job_tracker.

Partially implements: blueprint edp-plugin-communication

Change-Id: I7f9e510298d6f61f799792b4bacb906a93f7ef2c
Added scaling parameters to HDP plugin config

Added SCALE_EXISTING_NG_COUNT and SCALE_NEW_NG_COUNT parameters to HDP plugin
config. The default behavior remains as before, but an additional option
is added. Cluster scaling is parameterized in order to add an ability
to re-use cluster scaling test in performance/benchmark testing.

Change-Id: Iba1570f978e4f44046e64f1d38b2f498e7a0c421
Merge "Removed EDP dependency on job_tracker instance"
Add Hadoop 2 vanilla plugin

Features:
* deploy services: namenode, datanode, resourcemanager, nodemanager
* provisioning configs

Partially implements blueprint: vanilla-plugin-hadoop-2

Change-Id: I0c62050767e3c63bdfc9e1e0f3454abc4f070e26
Merge "Added scaling parameters to HDP plugin config"
Updated features comparision heat with direct engine

Change-Id: If2f5a26d583bc220e15a4971e041ef7382d9de42