fix(ui): improve colors contrast in dark mode

[robertsLando]

Fixes #4091

[robertsLando]

@zackbcom got time to checkout this?

[coveralls]

Pull Request Test Coverage Report for Build 12866237943

Details

• 0 of 44 (0.0%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.02%) to 21.041%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/lib/utils.js	0	3	0.0%
src/plugins/vuetify.js	0	11	0.0%
src/components/nodes-table/nodes-table.js	0	30	0.0%

Totals
Change from base Build 12813824348:	-0.02%
Covered Lines:	3952
Relevant Lines:	19978

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💛 - Coveralls

[zackbcom]

I don't think the purple was adjusted for everything.

I mostly have issues with the dark purple with little area for the color
Examples:

Maybe we can scrap the color changes and adjust just those two items.
Make the Z-Wave Long Range Button have a solid color?

After looking at the green button with the white text, that might need to be adjusted a bit darker.
Maybe we can set it to dark text?
New changes:

new change with #1e1e1e

old change:

Before

After

It was fixes in settings though.

Before

After