clicking MAX in buy section populates too high Amount field

When clicking the MAX button, next to where the user can specify the amount to buy, the field is populated based on the current balance of the user's `rel` coin.

This is confusing, because there are not always enough orders in the orderbook to fulfill that amount of `rel` coins.


As a user, i would expect that `MAX` button to populate field with the maximum amount of `base` that the orderbook allows to buy; in this case `39.12439778`.