Allow kwargs for every series (e.g. disabled=true) and fix sorting of y_axis keys

Tests passing and demoproject looks okay but I'm unsure because I removed various special cases here. Please have a close second look at this.

I mainly wanted to provide extra data for every series to disable some of them by default and did not understand why "series kwargs" are only possible in some cases.

The kwargs handling still looks a little dangerous as series kwargs shadows the kwargs provided as parameter but I'm not sure if this is a problem (maybe it's okay to just rename the parameter as it is not used anyway?).