Mocking module

Mocking module should mock user's message or message that he's replying to
ex:
`$mock moje zprava na mockovani` should produce smth like `mOjE zPrAvA nA mOcKoVaNi`
`$mock` used when replying to a message should mock referred message

Preferrably for someon with close to zero experience with TS & bot dev.

No files or tests are named. Locate the mocking module and the command handling for user messages and replies, then verify that `$mock text` transforms the supplied text and that `$mock` while replying transforms the referred message.

Written by the indexing model from the issue text.