Update README for clarity and to remove redundancy

Addresses concerns presented in issue #1157

README

@@ -19,11 +19,10 @@
 
     ~ What do I need?
 
-      Jinja 2.4 and Werkzeug 0.7 or later.
+      If you do `pip install Flask`, `pip` or `easy_install` will
-      `pip` or `easy_install` will install them for you if you do
+      install all dependencies. I encourage you to use a
-      `pip install Flask`.  I encourage you to use a virtualenv.
+      virtualenv. Check the docs for complete installation and
-      Check the docs for complete installation and usage
+      usage instructions.
-      instructions.
 
     ~ Where are the docs?