Make Emoji img attributes configurable

[JuanitoFatas]

Resolves #234

This Pull Request makes img tag attributes configuarable:

• Keep old behavior
• Clear attribute you don't want, set to nil ("height" => nil, "width" => nil, "align" => nil)
• Override / Clear img tag attributes
  • Override by passing hash, e.g. "draggable"=> false
  • Attribute value also accepts proc-like object with name argument
• [x] patch version bump because we're compatible with old behavior => 2.4.2
• These deprecated img attributes (height='20' width='20' align='absmiddle') can be removed when there is a next major / minor version bump

@jch What do you think?

[JuanitoFatas]

@jch Thanks for the review, updated in 1b3e5e4 :)

[JuanitoFatas]

If you think this is mergable, I will squash commits, merge into master. Add an changelog item and release a patch version :)

[jch]

I will squash commits, merge into master. Add an changelog item and release a patch version :)

Sounds good! Thanks for tackling this.

[JuanitoFatas]

Merged as 3518bbb.

[kbrock]

Thank you @JuanitoFatas - this was a much needed feature and looks great