[twgit] Init feature 'feature-90': Add stable origin tag on feature description.
add git describe on display branch
#90 minor, some colors
Add some unit tests around remove_feature() and remove_demo() functions.
#71
Merge branch 'feature-90' into feature-71
Simplify demo list.
#71
Factoriez feature start and demo start.
Factorise les opérations de merge_feature_into_branch().
#71