Client for EIA ESOD data

[aschn]

EIA Electric System Operating Data has an API for the hourly load (actual and forecast), generation, and imports/exports from all balancing authorities in the lower 48 states! This is an amazing complement to the data provided from the ISOs themselves.

To implement, create a file pyiso/eia_esod.py and add a new client class with the standard methods get_generation, get_load, and get_trade. Each method should take a balancing authority abbreviation as an argument, similar to how some get_lmp methods take a node name. All returned data should be in the RTHR and DAHR markets, and generation should be fuel other.

The query browser will be useful for writing the parsers, eg http://www.eia.gov/opendata/qb.cfm?category=2122628&sdid=EBA.CISO-ALL.D.H

Also check out their amazing docs! http://www.eia.gov/beta/realtime_grid/docs/UserGuideAndKnownIssues.pdf

[andydevlinsmith]

Just an update that I'm still working on this. Hoping to have a PR up soon.

[r24mille]

@ajdonnison, this issue can be closed since it was implemented with #109 and #118.