Add new feature to load custom rules

[sergicontre]

The objective would be to include using the parameter 'modules' , new modules with custom rules.
For example, performance custom rules , or specific polymer applications that the developer needs to incorporate.

Rule: detect bad use of addEventListener instead of this.listen.
Rule: not remove listen in components.
etc...

Example: polylint my-component.html --modules /lib/performance-rules.js

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[sergicontre]

I signed it!

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