[NEW] Collapseable messages for long messages
Closes RocketChat/feature-requests#759
In this PR I've added the feature for long message to be collapseable. Currently, it renders itself collaseable at messages being > 100 chars length. There is also a title to the collapsed message which is taken by using the first few characters of the original message.

@tassoevan @sampaiodiego
@supra08 I guess that <summary> tag should not be used as it is currently not supported in Microsoft Edge.
Hi @supra08! Sorry for the delay, we're gonna figure out how to add this feature to the app. Thanks a lot for the help!
Hi @supra08, really nice suggestion! We are working internally to improve our message layout and will consider your idea on it! As soon as we have an update about it will share it here. Thanks for your help!
Hey everyone,
I think this would be a nice feature and wanted to ask, if it is foreseeable when this PR will be merged. (No pressure, just curious)