Same-T Fund functionality

[grctest]

Is your feature request related to a problem? Please describe.

Same-T Funds were introduced to Bitshares, however they're unsuported by the reference wallet.

Describe the solution you'd like

Construct multi-operation transactions which borrow, utilize and then repay same-t funds.

Enable users to create same-t funds from within the reference ui.

Describe alternatives you've considered

Use the Bitshares Astro UI - both aspects of same-t funds are fully implemented in that user interface.

Additional context

This functionality is going unused - if the reference wallet implemented support perhaps people would use it.