Fixed small errors in INSTALL.txt

INSTALL.rst

@@ -10,11 +10,11 @@ For production use you surly want a real web server that supports WSGI
 
 QUICK INSTALLATION FOR THE IMPATIENT
 ====================================
-- python -m venv ./etc/python
+- python -m venv ./env/python
 - source env/python/bin/activate
 - python -m pip install -r requirements.txt
 - python -m pip install -e .
-- django-dav-events-admin setup ./env/django
+- django-dav-admin setup ./env/django
 - python ./env/django/manage.py enable_module dav_auth
 - python ./env/django/manage.py enable_module dav_events
 - python ./env/django/manage.py enable_module dav_registration