Feat: Reflecting changes with git checkout branch

[Amit0617]

I almost took it for granted in latest text-editors with changing branch in terminal, editors also shift to the changed branch but remix still caches old branch content and when shifting back to old branch I saw difference cached from it got overwritten on current branch. This creates problem like every time I want to change branch I would have to close remix, change branch and then reopen remix then it will get current state automatically.

[Amit0617]

Looks like there are already issue reported @mushketyk #149 #150 #151 #152 #153