feature #1215 Macros changes removal (fabpot)

This PR was merged into the master branch.

Discussion
----------

Macros changes removal

This PR reverts the changes made to macros in 1.14.

The initial PR looked massive and I was not comfortable with the changes, but I merged it anyways. But the latest PR about fixes some bugs in the implementation -- and adding some more changes (#1213) really scares me.

So, instead of continuing doing big changes, I prefer to revert everything for now, release 1.14 and give more time for these changes to mature and eventually be merged again.

Commits
-------

74586e9 Revert "merged branch hason/macros (PR #1139)"
bf40fa3 Revert "updated CHANGELOG"
c3e05f3 Revert "added an exception when a macro re-uses the same argument name twice"
524e406 Revert "renamed an internal variable"
60b575f Revert "fixed some unit tests"