Pass data objects into ggplot call

[sirrice]

Current version of ggplot() takes a variable name as input, by default "data", and relies on ggsave()'s prefix argument to set the data object.

ggplot('data', aes(...)) + ggsave(..., prefix=data_py(dataobject))

Modify ggplot() call to accept a data object as input, and let it configure the prefix under the covers. ggsave's prefix argument option can still be used for full control

[depristo]

sirrice, btw, I'm going to handle all of these open issues. Just put them here for proper bookkeeping

[depristo]

Oops, didn't realize this was a distinct issue. Happy if you want to handle this one.

[sirrice]

Cool. I'll wait for your better to_r set of functions, then tackle this.