Improvements to Sol and Luna themes

Hey @bling
   
I have made some changes to to improve the colour highlights, have a look and feel free to merge them ! 

Thanks ! 


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P.S. : I had **not** fetched the upstream changes for quite some time, and so before I made my updates to the fork, I fetched the upstream (and then ```git merge upstream/master```) and then finally made my changes, Git (or rather GitHub) seems to think I have two merges to send with this pull request, (I'm not sure why :sweat_smile: !). You should look to merge this commit  : 381ba9699167588694837fad1756ac9f2cb793e3 specifically, since that commit has the changes that I made ! 

Thanks once again ! :smile: