ControlValueAccessor implementation + Angular upgrade

[biologeek]

Hi Dan,

I made a fork of you color picker for one of my projects. I thought you may be interested in my changes.

Tu summarize, I added ControlValueAccessor support to your component so that it can be used in forms and modified some inputs so that component parent can inject its own set of colors.

Also, I upgraded to Angular 7 (just because I needed the keyvalue pipe but it may be useful for other reasons).

Anyway, thanks for your work on this component !

[chitgoks]

by any chance, does your lib actually float the colors? what i noticed with his library is that instead of the popup, they do show but the html fields below it get pushed down instead of the color picker floating as a dialog.