Upgrade openssl
Add m4

The package inserts m4 into the PATH if used as dependency.
GMP: depend on m4

Fixes #43.
Refactor Python packages

Most of our Python packages are importing from distutils_package, not
python_package. This is probably a good thing, as I don't really want to
deal with all the complexity that .eggs bring us with comparatively
little return.

[1] Explicitly add the setuptools dependency to anything importing from
setuptools (such as our python_package base recipe).  As I've mentioned
in the past, distribute is has been merged into setuptools and is now
deprecated, and the dependency on setuptools should be encoded in the
base package.

[2] Rename the base packages to:

- distutils_package (generic, uses native distutils installer)
- setuptools_package (inherits and overrides distutils_package, uses
setuptools installer)

Action: Rename python_package -> setuptools_package.

[3] Remove the distribute package completely from the repository.

[4] Set any Python package that doesn't rely on setuptools to install to
use distutils_package.

We should still do an audit of our current package base for this.
incorporate @certik suggestions
Merge pull request #215 from hashdist/ahmadia/refactor_python_packages

Refactor Python packages
Update matplotlib to version 1.3.1.

I added a licence field as discussed in
https://groups.google.com/forum/#!topic/hashdist/aJQkqm9hZZw
Sort travis test cases alphabetically.
Separate out testcase for matplotlib.
add verify functionality to matplotlib build
Merge pull request #214 from hashdist/openssl

Upgrade openssl
Merge pull request #217 from hashdist/m4

Add m4
Merge pull request #1 from hashdist/ahmadia/add_matplotlib_travis

add verify functionality to matplotlib build
Fix a comment
Don't delete pth files after install.

pth files are required for namespace packages.
Merge pull request #213 from lanewittgen/master

Update matplotlib to version 1.3.1.
matplotlib v1.3.1 fixes for Cygwin
Merge pull request #221 from hashdist/ahmadia/matplotlib_fix_cygwin

matplotlib v1.3.1 fixes for Cygwin