Remove variation selectors

[damienalexandre]

Variation selector break the synonyms.

Tried:

"cleaning_char_filter": {
          "type": "mapping",
          "mappings": [
            "\uFE0E=>",  
            "\uFE0F=>"
          ]
        }

But it does works.

To test with the modifiers and ZWJ too.

[damienalexandre]

Solution here: https://found.no/play/gist/195cd340c6600a6d26f1

I had to read Java code to find this, omg.

Better solution here: https://found.no/play/gist/4a8c6357e3bcb1ef8a6d