mmix: use full path of executable

Closes #29414.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
pyenv 0.4.0-20140520

Changes:

* python-build: Add new CPython release; 3.4.1
* python-build: Update default pip version (1.5.5 -> 1.5.6)
pyenv: add 20140520 bottle.
mmix: update 20131017 bottle.