Add wallet height to bottom toolbar

[hal0x2328]

What current issue(s) does this address, or what feature is it adding?
Monitoring wallet height requires getting all the wallet info which can be slow depending on how many address/tokens/contracts exist in the wallet

How did you solve this problem?
Added the current wallet height to the bottom toolbar in the same format neo-cli uses (wallet height/db height/blockchain height)

How did you make sure your solution works?
Manual testing

Are there any special changes in the code that we should be aware of?
No
Please check the following, if applicable:

• Did you add any tests?
• Did you run make lint?
• Did you run make test?
• Are you making a PR to a feature branch or development rather than master?
• Did you add an entry to CHANGELOG.rst? (if not, please do)

[hal0x2328]

Wallet._current_height seems to always be one higher than the db/blockchain heights. Does this track? Should I modify the height to subtract 1 for display purposes to avoid confusion?

[coveralls]

Coverage remained the same at 86.571% when pulling 340fe3a on hal0x2328:development into b8105d0 on CityOfZion:development.

[ixje]

I actually encountered this issue yesterday as well in my asyncio branch.
If you could change this

neo-python/neo/Wallets/Wallet.py

Lines 653 to 662 in fe90f62

	while self._current_height <= Blockchain.Default().Height and (block_limit == 0 or blockcount < block_limit):
	block = Blockchain.Default().GetBlockByHeight(self._current_height)
	if block is not None:
	self.ProcessNewBlock(block)
	else:
	self._current_height += 1
	blockcount += 1

to this

            while self._current_height < Blockchain.Default().Height and (block_limit == 0 or blockcount < block_limit):

                block = Blockchain.Default().GetBlockByHeight(self._current_height)

                if block is not None:
                    self.ProcessNewBlock(block)
                else:
                    break

                blockcount += 1

and a single wallet rebuild will be enough

at least that way we avoid confusion when looking at the toolbar code

[ixje]

see comment

[hal0x2328]

Ok, made the requested change

[ixje]

👍