Global plugin config values are not being set properly

[jcooklin]

When snap is started with a config and a plugin has a config item with a default value the value provided in the config (the one snap was started with) should override the plugins default value.

Given: snapteld --config config.yml
Run: snaptel task create -t task.yml

config.yml:

---
control:
  plugins:
    collector:
      mock:
        all:
          name: jane

task.yml:

---
version: 1
schedule:
    type: simple
    interval: 1s

workflow:
    collect:
        metrics:
            "/intel/mock/foo":

Current result: The above will result in the config{'name': 'bob'} being associated to /intel/mock/foo

Expected result: The config on /intel/mock/foo should be {'name': 'jane'}