MWEB-850

* added unit tests for ContributionMenuController,
* added new item in the menu if maps are enabled,
* created new JS file which is loaded on every page view (`WikiaInteractiveMapsCreateMap.js`),
* extracted some common logic from `WikiaInteractiveMaps.js` to utils,
* created new module `intMapConfig`,
* added tracking for different create map entry points.

@macbre, do you mind checking the unit tests, please? We talked about them yesterday and I'd like you to take another look at it :)
What do you thing about this?
```PHP
$mapsAssets = ['int_map_contribution_button_create_map_js'];
array_unshift( $mapsAssets, ( self::isSpecialMapsPage() ? int_map_special_page_js : int_map_parser_tag_js ) );

$assetsArray = array_merge( $assetsArray, $mapsAssets );

```