Any map list validation

[jaredoconnell]

Allows schemas in lists and maps, ensures that values are valid values, and ensures that values are homogeneous when necessary.

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[dustinblack]

Functional test successful with:

    wait_for:
      a: !wait-optional $.steps.stressng_loop.outputs
      b: !wait-optional $.steps.sysbench_cpu_loop.outputs
      c: !wait-optional $.steps.sysbench_memory_loop.outputs
      d: !wait-optional $.steps.fio_loop.outputs
      e: !wait-optional $.steps.coremark_loop.outputs
      f: !wait-optional $.steps.autobench_loop.outputs