Finish picker settings tab

[motorlatitude]

Picker tab under settings currently has no content.

This should have settings for two different picker styles as well as an input to set the polling interval for slower computers to handle the polling interval.

• Option to ctrl-click to automatically create a new palette with selected color
• Two different picker styles
• Input to change polling interval to track mouse

[motorlatitude]

Ctrl-Click functionality added in 900cca8

[motorlatitude]

Polling rate setting input has been added to the picker settings tab in c7991ee