Cast import fromlist to str to remove unicode types

Cast fromlist argument in import function to str to prevent unicode
types from causing it to choke and throwing a TypeError.
Add tests around casting import function to str

Add tests to ensure that __import__ fromlist is called with a str and
not a unicode type.
Remove unneeded mocks in unicode path import tests

Rather than creating mocks to construct fictitious scenarios, the tests
now use real examples to ensure this works as expected.
Merge pull request #2 from WebFilings/fix_import_error

Remove unneeded mocks in unicode path import tests
Merge branch 'master' of wfgithub:WebFilings/furious into fix_import_error
Fix non-testing unit test and simplify str-ification of module

After much pain and poking, it was discovered that the non-str import
bug only impacts modules, and not items within modules.  This led to
very flaky import behavior.  Also corrected the unit test for this to
work *slightly* more reliably.
Switching to use markdown in a unit test for travis
Create a module for use in unicode import test
Merge pull request #78 from WebFilings/fix_import_error

Fix import error