Support plugin arguments

[k82cn]

Is this a BUG REPORT or FEATURE REQUEST?:

/kind feature

Description:

Currently, we only support configuration on plugin's callback; it's better to support customized arguments to plugins. For example:

actions: "reclaim, allocate, backfill, preempt"
tiers:
- plugins:
  - name: priority
  - name: gang
  - name: conformance
- plugins:
  - name: drf
  - name: predicates
  - name: proportion
  - name: nodeorder
    arguments:
    - affinity.weight: 2

[k82cn]

@thandayuthapani , would you help on that?

[thandayuthapani]

@k82cn we can handle arguments as map instead of parameters being slice, since those parameters can have different keys for different plugins. affinity.weight might be only suitable for nodeorder plugin. So we can handle it as map, so in code we can try to get it from map.

[thandayuthapani]

Expected YAML should of this form, arguments are handled as map instead of slice.

actions: "reclaim, allocate, backfill, preempt"
tiers:
- plugins:
  - name: priority
  - name: gang
  - name: conformance
- plugins:
  - name: drf
  - name: predicates
  - name: proportion
  - name: nodeorder
    arguments:
      affinity.weight: 2
      affinity.enable: true