LRDOCS-1184 intro.markdown created for liferay mvc portlet folder.
LRDOCS-1184 Conveted devguide portlet creation section into a tutorial and migrated image.
fixed Next Steps URLs
Intro for JSP portlets using Liferay MVC
Move portlet namespacing tutorial to jsp-portlets
Move portlet preferences tutorial to jsp-portlets
Delete platform-frameworks section of tutorials.
Remove unneeded next steps content
Merge branch 'LRDOCS-1184' of https://github.com/mwilliams2014/liferay-docs into jsp-portlets
LRDOCS-1184 Rename section folder to liferay-mvc-portlet
LRDOCS-1184 Edit liferay-mvc-portlet intro
LRDOCS-1184 Edit creating-a-liferay-mvc-portlet tutorial.
Move portlet prefs and namespacing tutorials into liferay-mvc-portlet.
Merge pull request #964 from jhinkey/liferay-mvc-portlet

Intitial Liferay MVC portlet tutorials