combine legacy roadmap documentation into one

Author: titusfortner

website_and_docs/content/documentation/legacy/selenium_2/roadmap.en.md renamed to website_and_docs/content/documentation/legacy/developers/roadmap.en.md

@@ -1,11 +1,14 @@
 ---
-title: "Snapshot of Roadmap for Selenium 2"
+title: "Snapshot of Roadmaps for Selenium Releases"
 linkTitle: "Roadmap"
 weight: 15
 description: >
-    The list of remaining items toward the end of Selenium 2.0 development
+    The list of plans and things to accomplish before a release
 ---
-This documentation previously located [on the wiki](https://github.com/SeleniumHQ/selenium/wiki/RoadMap/eef12bca5fdc865449ad2d1735ee08e40ba0bd2b) \
+
+## Preparation for Selenium 2
+Date unknown
+This documentation previously located [on the wiki](https://github.com/SeleniumHQ/selenium/wiki/RoadMap/eef12bca5fdc865449ad2d1735ee08e40ba0bd2b)
 
 The following issues need to be resolved before the final release:
 
@@ -20,8 +23,39 @@ The following issues need to be resolved before the final release:
 
 A final release will be made once these are implemented in Firefox, IE and at least one webkit-based browser.
 
-## The Future
+### The Future
 
 The following are also planned:
 
 * **JsonWireProtocol** --- The formalisation of the current RemoteWebDriver wire protocol in [JSON](http://www.json.org/).
+
+## Preparation for Selenium 3
+As of Mar 16, 2015
+This documentation previously located [on the wiki](https://github.com/SeleniumHQ/selenium/wiki/Shipping-Selenium-3)
+
+### User Visible Changes
+* Migrate all drivers to use the status strings rather than status codes in responses
+* Update client bindings to also cope with that
+* Write a new runner for the html-suite tests
+* Segment the build to remove RC
+
+### Clean up
+
+* Using WebDriver after quit() should be an IllegalStateException
+* Actions to have a single end point
+* Capabilities to be the same as the spec
+* Multiple calls to WebDriver.quit() should still be safe.
+* Clean up WebDriver constructors, pulling heavy initialization logic into a Builder class
+* Migrate to Netty or webbit server
+* Delete unnecessary cruft
+* Land a cleaner end point for the rc emulation
+
+## Preparation for Selenium 4
+This documentation previously located [on the wiki](https://github.com/SeleniumHQ/selenium/wiki/RoadMap)
+As of April 12, 2017
+
+- Finish the [W3C WebDriver Spec](https://w3c.github.io/webdriver/webdriver-spec.html)
+- Implement the local end requirements for the spec in selenium
+- Implement protocol conversion in the standalone server
+- Ship 4.0
+-