Upgraded parent pom to version 7; removed assembly plugin; removed clover profile

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@1512192 13f79535-47bb-0310-9956-ffa450edef68
An attempt at finding a work-around for a bizzare issue that affects on one unit test when executed by Continuum CI server

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@1512197 13f79535-47bb-0310-9956-ffa450edef68