Allow to filter optimized fonts with an allowlist and a skiplist

[Moustachos]

Add two options: allowedFilesRegex & skippedFilesRegex.

Both can be null or RegExp, they're mutually exclusive and allowedFilesRegex has priority over skippedFilesRegex.

Usage example (to only target FontAwesome):

const FontminPlugin = require('fontmin-webpack')

Encore
  .addPlugin(new FontminPlugin({
    allowedFilesRegex: /^fa-/
  }))

Fix #29
Fix #5

[patrickhulce]

thanks @Moustachos, looks great ! could you add a quick test for this?

[Moustachos]

There you go :)

[patrickhulce]

thanks @Moustachos !

[patrickhulce]

heads up @Moustachos we have a lint failure, but LGTM other than that

[Moustachos]

@patrickhulce it should be fixed now

[Moustachos]

@patrickhulce could you merge this one when you got some time?

I also made a pull request on Fontmin lib to address a bug where invalid code points are pushed to output, due to of how code points uniqueness is checked (ecomfe/fontmin#92).

It's been merged in 0.9.9 so if you could upgrade it while you're at it, it would be sweet 👍

[patrickhulce]

thanks for the ping @Moustachos!