Steps to manage a feature branch that has a dependency on another feature branch

branch off feature branch

A--BC   <-- master
 \
  B--C   <-- feature-1
      \
       D--E   <-- feature-2

after feature-1 merges into master, and whilst on feature-2 use:
`git fetch origin`
`git rebase --onto origin/master feature-1`

--onto will tell Git to copy commits D and E (only) with the copies going after commit BC, like this:

      D'-E'  <-- feature-2 (HEAD)
     /
A--BC   <-- master
 \
  B--C   <-- feature-1
      \
       D--E   (now abandoned)