* refactor most regarding commit and staging
* use gitgraph 1.2.3
* move db gui to new include
* allow specifying branch
* move target branch to stage object
* git, get rid of reference to repo
* merge now working #275
cleanup
* merge #275, scaffolding
* refactoring few gui pages
top class element moved to page_super
* syle FORM dropdown
* find common ancestor
* calculate merged tree #275