Add branch dropdown 2

This new feature has the purpose to have a list of all the branches in a place and allow to easily checkout a desired branch. This component is based on the "remote" component. It used the same UI and a big part of the code. 
For the moment, no tests are implemented. 
In the future, it would be great to add a search box to this component with an autocompletion, so it will be easier to   search a branch if you have a lot of branch.