Fix travis.yml; use py.test and install dev-requirements

Fixes #25

{{cookiecutter.app_name}}/.travis.yml

@@ -6,8 +6,6 @@ python:
   - "3.3"
   - "2.7"
 
-# command to install dependencies, e.g. pip install -r requirements.txt --use-mirrors
-install: pip install -r requirements.txt
+install: pip install -r requirements/dev.txt
 
-# command to run tests, e.g. python setup.py test
-script: nosetests
+script: py.test tests

{{cookiecutter.app_name}}/{{cookiecutter.app_name}}/settings.py

@@ -4,7 +4,7 @@ import os
 os_env = os.environ
 
 class Config(object):
-    SECRET_KEY = os_env['{{cookiecutter.app_name | upper}}_SECRET']  # TODO: Change me
+    SECRET_KEY = os_env.get('{{cookiecutter.app_name | upper}}_SECRET', 'secret-key')  # TODO: Change me
     APP_DIR = os.path.abspath(os.path.dirname(__file__))  # This directory
     PROJECT_ROOT = os.path.abspath(os.path.join(APP_DIR, os.pardir))
     BCRYPT_LOG_ROUNDS = 13