Return all conditions codes via 1 API call, include aggregation rules.

**Is your feature request related to a problem? Please describe.**
Retrieving all [Conditions Codes](https://docs.alpaca.markets/reference/stockmetaconditions-1) requires 6 API calls (trade/A, trade/B, trade/C, quote/A, quote/B, quote/C). It's not much data, and I assume it changes rarely or never. Seems like we should be able to get all conditions with a single API call.

**Describe the solution you'd like**
Return all Condition Codes for trades and quotes and all tapes via a single API call. It would be especially nice if the response included aggregation rules similar to the [Polygon API](https://polygon.io/docs/stocks/get_v3_reference_conditions).

**Describe alternatives you've considered**
Using Polygon's API.

**Additional context**
There is useful info re: using conditions for aggregation here: [Stock Minute Bars](https://alpaca.markets/learn/stock-minute-bars/)