Removing the imports from package __init__ files

These are causing a lot of errors when one of the imports fail. Plus, it
doesn't seem like good practice since other packages don't do it.
Probably better to just import the modules from the packages in the
scripts.

Need to fix broken recipes and tests because of this.
Merge branch 'master' into package-imports
Fixed broken cookbook recipes package import

Some recipe were still importing a whole package and trying to get the
modules inside. The new convention is import modules directly.
Merge branch 'master' into package-imports
Merge pull request #76 from leouieda/package-imports

Removing module imports from subpackage __init__.py files