Merge branch 'nd/clear-gitenv-upon-use-of-alias'

Merge branch 'nd/clear-gitenv-upon-use-of-alias'

The automatic typo correction applied to an alias was broken
with a recent change already in 'master'.

* nd/clear-gitenv-upon-use-of-alias:
  restore_env(): free the saved environment variable once we are done
  git: simplify environment save/restore logic
  git: protect against unbalanced calls to {save,restore}_env()
  git: remove an early return from save_env_before_alias()