Add the directory and its subdirectories to Matlab’s path, dynamically,
with strippint out of .svn and .git directories.
Use for putting routines onto path that are specifict to a particular
project, without them staying around and clogging up the name space.
b) Direct call
7/12/13 dhb Wrote it.
7/25/14 dhb Make independent of BrainardLab idiosyncracies.