Republish the fixed apache extensions as google-http-client-apache-v2 (#637)

* Republish the fixed apache extensions as google-http-client-apache-v2

* Fix parent version

* Remove google-http-client-apache and google-http-client-apache-legacy

* Deprecate the public interfaces for the legacy apache extensions.

Deprecates the package com.google.api.client.http.apache
Deprecates the com.google.api.client.http.apache.AppacheHttpTransport
class.

* Clean up bom versions. Appengine artifact does not need to depend upon the apache artifact

* Fix assembly references to apache artifact

* Fix main dependency management config

* Fix license headers

* Update javadoc from review

* Declare explicit exceptions thrown in tests

* Rename test variables

* Replace StringUtils.getbytesUtf8()

Author: chingor13

google-http-client-android/pom.xml

@@ -48,9 +48,5 @@
       <groupId>com.google.http-client</groupId>
       <artifactId>google-http-client</artifactId>
     </dependency>
-    <dependency>
-      <groupId>com.google.http-client</groupId>
-      <artifactId>google-http-client-apache</artifactId>
-    </dependency>
   </dependencies>
 </project>