[FEATURE] Modify price and/or amount of an order

New format options for rpamount filter:

hard_precision: do not allow precision & min_precision to be overridden.

tiny_precision: for very small numbers e.g if set to 5 would format:
0.000000000012866401 as 0.000000000012866
[FEATURE] Modify price and/or amount of an order

New optional attribute rpShow that specifies a function to call to
determine whether to show popup e.g. for pre-checks.
[FEATURE] Modify price and/or amount of an order

model.ready property indicates whether both Bids & Asks are ready.
[FEATURE] Modify price and/or amount of an order

Support for editing an order in "My Orders" on the Trade tab.
Either the price or amount (quantity) or both may be edited in place.
If the user confirms the change, the order is cancelled and then
replaced with a new order with the changed values.
Merge pull request #1851 from bss-/trade-modify-order

[FEATURE] Modify price and/or amount of an order