Allow to pass provider arguments to getDocument()

The `getDocument()` method of the abstract scraper now accepts custom URL pattern and placeholder values instead of always getting those from the same place with a call to `getProviderArguments()`.

The method falls back to the previous behavior if no pattern is passed.
Allow to pass HTML doc & charset to getCrawler()

The method now accepts HTML code to feed the crawler. If nothing is provided, it falls back to the previous behavior of getting a document by itself.

The Committee scraper is also updated to match the new method signature.
Add ability to download committee page in any lang

This is needed in order to get the NL name of a committee.
Get FR and NL names in Committee scraper