Feature/paid auth extra commands

[giurgiur99]

Fixes #122

Changes proposed in this PR:

• New methods: Generate new auth token, invalidate auth token, deposit, authorize, withdraw, getUserFunds

[mariacarmina]

Will it be useful to have tests for generate auth token commands too?
Also for deposit in escrow command, maybe it is worthy to display to the end user how much available funds has in escrow and waits for its input (y/n) if the user still wants to deposit the amount, deposit action should not happen often (at every compute job) and I think it is useful to show to the user what already has in terms of funds.
EDIT: create a new command of checking escrow funds available, one for withdraw.

[mariacarmina]

A suggestion from my side to display the authorizations within check funds command (I do not mind if we'll change the name for the command to be more intuitive for the user).
Looks good, after this modification we can merge this.

Thank you @giurgiur99!

[mariacarmina]

LGTM!