note: see #5 to watch it fail

- deprecates the CLI, not needed and adds maintenance efforts

- deprecates the changing of ownership of a vest / lockup (not needed
and causes edge-cases)
- also erases related JS codebase to call it

The original codebase corresponds to a Vesting Contract between A and B,
in which A gives tokens to B in a scheduled way. The intended behaviour
of this proposal is for A to lock tokens, that only A can withdraw.

Following that intended behaviour, we deprecate the concept of
"destination" from every call (as it will be same as the source).

The original codebase https://github.com/Bonfida/token-vesting supports
an array of Dates to define a Vesting Contract. In that way, it can say:
"unlock 10 at May 10, 10 at May 20, ..." and so on.

The intended behaviour is to have only 1 Date per vesting / lockup, this
PR replaces the Schedules<> array for a single Schedule, and deprecates
the variable `number_of_schedules`

The underlying codebase requires the user to decide at lockup the Date
of withdrawal.
The intended behaviour, is that the user can decide to lock the tokens
in an "unlocked with withdrawal period" mode, in which it would require
the user to first "initiate the withdrawal", to be able to actually
withdraw the tokens (e.g.) 7 days later.

This is achieved by:
- reverting on withdrawal when locking Date is 0
- adding a new method, identical in arguments to "unlock", that would
revert if Date != 0
- when user calls this method, the locking Date should be `now() + 7
days`

Only a set of possible time-deltas should be allowed (e.g.) 0 (for
unlocked with withdrawal period), 1 month, 3 months, and so on... The
locking method should revert if the user tries to lock for a different
amount of time.

This PR replaces the concept of Dates when creating a lockup, since the
user will be inputting a TimeDelta, and internally we should calculate
the Date, to keep the same infra as it was.