Added a couple notes

Micro-Python-on-Mac-OSX.md

@@ -14,7 +14,9 @@ In order to compile on OSX you will need the following software packages install
 * libffi (minimum version 3.1-4 from Macports) `sudo port install libffi`
 * pkgconfig `sudo port install pkgconfig`
 * Python >= 3.3 `sudo port install python34`
-* git - to keep local source tree up to date
+* Setup python34 as python3 `sudo port select python3 python34'
+* git - to keep local source tree up to date `sudo port install git`
+* If you like using git completion or `$(__git_ps1)` for your prompt, then add the following line to your ~/.bashrc file: `. /opt/local/share/git/contrib/completion/git-prompt.sh`
 
 ## Build Process
 Same as on Linux - go to `micropython/unix` and run `make` (or `make -B` or `make clean; make` if rebuilding.