Testing updates

[sashadev-sky]

Fixes #389 (<=== Add issue number here)

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• remove jshint only use eslint
• moved TESTING.MD into wikis and updated it
• lint specs
• bump 0.21.7 -> 0.21.8

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[sashadev-sky]

@jywarren @VladimirMikulic linted our test files and removed jshint because we already have eslint