Amounts in decimal format

[kroggen]

Currently some functions on smart contracts accept amounts with unit, like:

1 aergo
15 aergo
200 aergo

But when we specify a decimal amount like "1.5 aergo", they are not recognized.

This pull request adds support for amounts in decimal format to the Aergo engine

So they could also support this format:

0.021 aergo
0.5 aergo
13.9 aergo

The amounts must contain the "aergo" unit. Decimal format is not valid for gaer and aer

The above change applies to these functions inside smart contracts:

contract.send()
contract.call.value()
contract.deploy()

As well as these 3 commands in Composable Transactions:

call-send
pcall-send
send

And also to these commands on brick:

inject
getstate
send
call
deploy