Enable option to set minion scheduler

[mecavity]

Tested on CentOS 7

An example:

minion:
  schedule:
    - highstate:
      - function: state.apply
      - minutes: 60
      - returner: redis

Would result to:

schedule:
    highstate:
      function: state.apply
      minutes: 60
      returner: redis

[aboe76]

@mecavity could you add the examples to the pillar.example for references.

[mecavity]

@aboe76 Done, anything else?

[aboe76]

@mecavity thanks, merged it