Merge with SD (add passive and array validator)

[ljqx]

1. fixes of string and number validator.
2. passive and array validator and corresponding tests.

[ljqx]

@lyweiwei , this change adds passive validator which is needed by ko-schema.

[coveralls]

Coverage decreased (-16.2%) to 83.81% when pulling ccc9c9b on ljqx:merge-with-SD into df1a627 on Microsoft:master.

[lyweiwei]

@ljqx could you add some test cases to silence coveralls?

[ljqx]

@lyweiwei , sure.

[coveralls]

Coverage remained the same at 100.0% when pulling 00d0fa2 on ljqx:merge-with-SD into df1a627 on Microsoft:master.

[coveralls]

Coverage remained the same at 100.0% when pulling 774e488 on ljqx:merge-with-SD into df1a627 on Microsoft:master.

[ljqx]

@lyweiwei , I've imported some code of component/humanize in this PR, for keeping the coverage, I commented out unused code in it.