Switch from distutils-extra to setuptools and setuptools-gettext

Some refactoring of the project layout is required, such as:
- Moving data/ under the variety package (it needs to be there for setuptools to pick it up)
- setuptools-gettext generates variety/locale from po/ as part of the build. Add it to gitignore

Author: jlu5

.gitignore

@@ -8,6 +8,7 @@ __pycache__/
 *.py[cod]
 *$py.class
 .pybuild/
+variety/locale
 
 # C extensions
 *.so

README.md

@@ -60,7 +60,7 @@ sudo apt install variety-slideshow
 To build Variety from source, you will need the following:
 
 - setuptools
-- [python-distutils-extra](https://launchpad.net/python-distutils-extra)
+- setuptools-gettext
 
 #### Runtime Requirements
 

data

@@ -0,0 +1 @@
+variety/data