added "colour selector" replacing slider for "hue" parameter

[manmohan777]

I think selecting hue using a color selector is easier than a slider so I created a custom color selector and replaced the slider with the "hue" parameter.

[CLAassistant]

All committers have signed the CLA.

[manmohan777]

PaletteBar View enabled and disabled state

[shahpiyushv]

@manmohan777 , thanks for the contribution. Something like this would definitely be useful as people can relate to visual colour more than the arcdegree value. However, this is not matching with rest of the theme of the app. Would it be possible to use something like this slider?

Moreover, the same UI element also needs to show up in the Schedule actions' screen. Internally, we are checking how we can better support this, so that contributors will need to add the UI element at only once place and not two.

[manmohan777]

hi Piyush, I can change its UI and make it look like a slider as you have demonstrated and create a new UI element then it will be available in the Schedule actions.

[manmohan777]

this is the changed ui

[manmohan777]

and in schedule section color selector looks like this

[shahpiyushv]

@manmohan777 this looks good now. I will have someone review this. Meanwhile, can you please squash your 11 commits into 1?

[shahpiyushv]

@manmohan777 , thanks for the contribution. This has now been merged.