Typo and grammar corrections

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk@1603505 13f79535-47bb-0310-9956-ffa450edef68
HTTPCORE-385: project license link to refer to http://www.apache.org/licenses/LICENSE-2.0.txt

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk@1603765 13f79535-47bb-0310-9956-ffa450edef68