Add an example profile for RHEL6

Fixes #418
Workaround h5py/MPI issue.

Ref: https://github.com/h5py/h5py/issues/439
Python Framework build on OS X, Clawpack example

This adds the ability to install Python as a framework.
This is needed for interactive plots, but is also somewhat fragile.
For example, the framework install breaks the current scipy build,
the two are incompatible.
Don't root-install Python framework applications
Add pip, ipdb
Merge pull request #505 from hashdist/ahmadia/python-framework

Python Framework build on OS X, Clawpack example
Merge pull request #492 from hashdist/ahmadia/fix_h5py

Workaround h5py/MPI issue.
Merge pull request #491 from hashdist/rhel6_example

Add an example profile for RHEL6
Update the RHEL6 example

Add subversion and swig with proper options.
Remove trailing whitespace
Merge pull request #510 from hashdist/rhel_example_update

RHEL6 example update
Merge pull request #509 from hashdist/ahmadia/add_pip

Add pip, ipdb