MAGETWO-91200: Update documentation for PageBuilder EAP

- create README.md

Author: tkacheva

README.md

@@ -0,0 +1,31 @@
+# magento2-page-builder
+
+# PageBuilder EAP
+
+We open access to PageBuilder code for Partners to:
+- explore extension points that PageBuilder provides in oder to build integration with native PageBuilder capabilities for 3rd parties (Facebook, Instagram etc)  and their own modules
+- try out PageBuilder customization options to grow its functionality beyond native features
+- Prepare to migrate clients from Bluefoot 1.0 to PageBuilder
+
+This program is _not design_ to build a website and go live using early code. 
+
+# PageBuilder Package 
+We offer 2 options to get the PageBuilder code:
+- Composer package - option for installing page builder if you do not plan to do any contribution into PageBuilder code repository 
+- GitHub repository - option to install page builder and contribute to the code 
+
+# Contribution to the PageBuilder
+We appreciate your direct contribution to PageBuilder repo. It can be either feature development or bug fix:
+List of known issues 
+
+# PageBuilder Updates from Magento Core Team
+Expect the code to be updated on regular basis (every 2 weeks) and be ready to the update introducing breaking changes. We want to limit that harm so we publish the backlog that core teams are going to work on next couple of months:
+link to the list of features
+
+# Feedback needed
+We want to know more how you would need to customize PageBuilder. Here is the list of topics that we are specifically interested in:
+Web Content API
+
+Join the PageBuilder slack channel to participate in technical discussions and ask questions 
+URL: magentocommeng.slack.com
+And ping Olena Tkacheva (https://magentocommeng.slack.com/messages/@UAFV915FB)