[feature] Added light/system theme

[alindt]

Added a light theme; not complete/optimized yet, but it's a start.

Fixes #412

[heisbrot]

Hey @alindt,

Thanks for your contribution!
Light mode is definitely needed and requested by many users.

I will look at your PR and see what we can do to push it for an initial version.
Probably will also need a "Beta" badge for it.

[markcst]

Hey @alindt,

Thanks for your contribution! Light mode is definitely needed and requested by many users.

I will look at your PR and see what we can do to push it for an initial version. Probably will also need a "Beta" badge for it.

Hi, @alindt , any news about it?

[daidi]

Hey @alindt,

Thanks for your contribution! Light mode is definitely needed and requested by many users.

I will look at your PR and see what we can do to push it for an initial version. Probably will also need a "Beta" badge for it.

any news? @heisbrot

[ChillarAnand]

Did you get a chance to look into it?

[ChillarAnand]

@alindt Can you resolve the conflicts and also add a beta badge?

@heisbrot This PR has been in pending state for a while. How can I help to get it merged?

[TechHutTV]

@ChillarAnand #658 this will get merged in a couple of weeks, needs a little more polish.