[WIP][NEW] Group same user messages

[Adizbek]

@RocketChat/android

Closes #712
As describe in issue:

Group messages:

Take in consideration the setting (Message_GroupingPeriod -> default is 900 seconds);
When there's a day separator, can't be sequential;
When a message is a system message (message removed, pinned message, permission changes, etc)
Users need to be the same in order to group it;

Some criteria not implemented yet.

Screenshots or GIF for the change:

https://youtu.be/3ciV8ZmTaE0