- withdrawable -> unlocked
"withdrawable" was a bad name, since these funds - while unlocked -
are not necessarily withdrawable if the voter is currently engaged in
a vote.
- only_deposit -> only_unlocked
Locked funds are technically also deposited. Make it clearer that this
is talking about the unlocked parts of the funds on the account.
Rename internal_transfer -> internal_transfer_locked
The new instruction can move only unlocked funds and is useful to avoid
needing to withdraw funds if they should be re-locked in a different
deposit entry.
Withdrawing can be impossible when a voter is engaged in proposals.