Add support for Put Credit Spreads

[bortoni]

Besides wheel, I am starting to also trade put credit spreads. Currently there is no way to even log buying a PUT. Is it out of scope to consider this use case for this tool?

Put credit spread:

Sell a Put at $X for credit
Buy a Put at $(x - width) for a debit

credit > than debit

Example:

Sell SPY put at $650
Buy SPY put at $649 (width = 1)

Collateral = width * number of contracts

[MarkT1065]

Thanks for the feedback! Yes, there's a distinct lack of support for buying options. This first iteration was straight "wheeling", which is to say selling options.

there's discussion in #17 about a new data model centered around "transactions" that would offer better support for buying options and more general trading.