Allow to copy to clippboard all text inside the chat

[grunch]

This is important because in the chat users send their bank account number to receive fiat

[Catrya]

completed in https://github.com/MostroP2P/mobile/releases/tag/v1.0.0%2B1-alpha-28

[grunch]

completed in https://github.com/MostroP2P/mobile/releases/tag/v1.0.0%2B1-alpha-28

I can't copy the text of messages in the chat, re-opened

[chebizarro]

Connected to issue #87