Calligraph

* Fix converting config options to dataframe when there are nested dictionaries in the config (e.g. `solve.solver_options`).
* CLI: default to random port, making it easier to run several instances in parallel

* Minor bug fixes: 0 values in timeseries may be dropped; summing should only happen when dim exists

* "Line" and "Duration" time series plot types
* Time series plots can sum by nodes or techs
* Time series plots don't break on models with only few timesteps
* Support models without a name

* Name changed to **Calligraph**
* Time series subsetting (1)
* Improved time series plotting on map page
* Zoom maps by zoom wheel (5)
* Permit changing the same colors together
* Various bug fixes and improvements

Initial release