Merge pull request #6782 from s0undt3ch/hotfix/absolute-imports

By enforcing absolute imports, there's no need for module name aliases.
handle gracefully -f (--find-links) in "pip freeze" and report error in output
not not!
Get the package name from `egg=<package-name>`. Refs #6643.
Since there's no state module rename, a `True` or `False` is good enough.
Switched arguments in `SaltReturnAssertsMixIn.assertInSaltComment()`
Switched arguments in `SaltReturnAssertsMixIn.assertNotInSaltComment()`
Switched arguments in `SaltReturnAssertsMixIn.assertNotInSaltReturn()`
Switched arguments in `SaltReturnAssertsMixIn.assertInSaltReturn()`
Use `pip.req` for parsing package requirements. Minimal tests.
Some more requirements parsing tests
Make sure package names are properly quoted.
Don't quote the package name in the state. It will properly quoted in in the pip module.
Another example test case.
No point on listing packages from pip freeze if there's no prefix to match against.
Corrected test case output.
Update documentation to the renamed pip state
By forcing absolute imports, we don't have to rename the pip state module.
Fix module name to import.
Explain why a system-wide pip needs to be available.