Zero 0.7.0 Known breaking changes: - Changed Response's `magnitude` property to return the absolute magnitude instead of the dB magnitude. The new `db_magnitude` property now provides the dB magnitude. - `mag_tick_major_step` and `mag_tick_minor_step` in `Solution._plot_bode` have been renamed `db_tick_major_step` and `db_tick_minor_step` and only work when `scale_db` is set. - Changed some plotting options in the default user configuration. - Changed the way solutions are combined to fix bugs when 3 or more solutions are combined. Now, by default, the groups that contain functions in each source solution are not combined, but kept separate in the new solution. Other changes: - Allowed singular filters when retrieving and plotting functions in a solution, such as "source" or "sink" (instead of just "sources" and "sinks"). - Added support for adding reference responses and spectra to solutions, which are plotted alongside functions. - Added support for creating custom responses and noise spectra (i.e. those not generated by an analysis, but from user-supplied data). - Added support for referring noise to the circuit input. - Added support for mathematical operations on functions. - Added support for generating noise sums with noise analyses. - Added support for filtering solution functions by their label. - Removed instances where function source or sink types were checked in solutions; now these can be strings. - `scale_db` parameter added to `Solution._plot_bode` to control dB or absolute scaling of response plots. - Added CLI flag to control response plot scaling. - Added a bunch of new configuration options, mostly regarding plotting. - Added a bunch of new examples demonstrating the new features. - Lots of documentation updates.