restructuring requirements to not pollute non-heroku environments with heroku specific requirements

Procfile

@@ -1,3 +1,2 @@
-release: pip install -r requirements_heroku.txt
 release: yes "yes" | python manage.py migrate
 web: gunicorn bakerydemo.heroku_wsgi --log-file -

readme.md

@@ -53,7 +53,7 @@ With PIP installed run the following commands:
 
     git clone git@github.com:wagtail/bakerydemo.git
     cd wagtaildemo
-    pip install -r requirements.txt
+    pip install -r requirements/base.txt
     ./manage.py migrate
     ./manage.py load_initial_data
     ./manage.py runserver

requirements.txt

@@ -1,5 +1 @@
-Django
-elasticsearch
-wagtail
-wagtailfontawesome
-Pillow
+-r requirements/heroku.txt

requirements/base.txt

@@ -0,0 +1,5 @@
+Django
+elasticsearch
+wagtail
+wagtailfontawesome
+Pillow

requirements/heroku.txt

@@ -1,3 +1,4 @@
+-r base.txt
 # Additional dependencies for Heroku deployment
 dj-database-url
 whitenoise

vagrant/provision.sh

@@ -25,7 +25,7 @@ su - vagrant -c "echo $PROJECT_DIR > $VIRTUALENV_DIR/.project"
 su - vagrant -c "$PIP install --upgrade pip"
 
 # Install PIP requirements
-su - vagrant -c "$PIP install -r $PROJECT_DIR/requirements.txt"
+su - vagrant -c "$PIP install -r $PROJECT_DIR/requirements/base.txt"
 
 
 # Set execute permissions on manage.py as they get lost if we build from a zip file