Initial commit of grading utilities
Add tests for client utils.
Add tests for AutograderConsole
Add grading_tests for run function
Some refactoring; mark private functions/classes with __
Minor refactoring to grading.py based on John's suggestions
Replace split function with textwrap.dedent/indent
Abstract testExec pattern in grading_tests
Abstract Autograder.run tests in grading_test.py
Improve docs of install.py
Merge pull request #51 from Cal-CS-61A-Staff/grading

Add grading utilities to client.
specify bash as shell in install.py
remove extra shell call
Merge pull request #60 from Cal-CS-61A-Staff/install

Improve docs and shell command for install.py
Changed models to KeyProperty from StructuredProperty. Fixed tests.
Merge pull request #62 from Cal-CS-61A-Staff/fixed_models

Changed models to KeyProperty from StructuredProperty. Fixed tests.
Merge branch 'master' into protocol-and-tests
Add tests for ok.py