Adds test to ensure external module asteval is installed and the expected version.
Adds more things to try in the README.
Merge pull request #128 from scottpurdy/master

Adds test to ensure external module asteval is installed and the expecte...
Merge branch 'master' into readme
Adds safe_interpreter module tests.
Merge pull request #129 from scottpurdy/readme

Adds more things to try in the README.
Merge branch 'master' of git://github.com/numenta/nupic
Fix broken test.
Import fix.
Merge pull request #130 from scottpurdy/master

Adds safe_interpreter tests