Pyeql

- Add method to calculate the total concentration of an element in a solution
- Add method to automatically generate certain solutions (like seawater)
- Add method to calculate the hardness of a solution
- Add method to calculate the alkalinity of a solution
- Add method to calculate the charge balance of a solution
- Add method to calculate the Bjerrum length
- Add database entries for hydrated and ionic radii of 23 commonions
- Add database entries for the 'B' parameter in the Jones-Dole viscosity equation for 20 common ions
- Add test suites for solute property methods, hardness, osmotic coefficient, and Debye length
- Improve logging system to work better when using pyEQL interactively
- Improved README with graphics and rich formatting
- Fix bug related to activity and osmotic coefficients for multivalent salts
- Fix bug related to retrieval of water properties
- Documentation enhancements and fixes

- Fix bug in get_amount() causing no output when mass-based units were specified.

- Add 93 entries to diffusion coefficient database
- Add 93 entries to Pitzer partial molar volume parameters database
- Add 130 entries to Pitzer activity parameters database
- Change extension for database files from .csv to .tsv
- Corrections and additions to the contributing documentation
- Uploaded to the Python Package Index for easier installation
- Add this changelog

- First public release