Updated project building instructions

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/branches/4.2.x@1481335 13f79535-47bb-0310-9956-ffa450edef68
Fixed typo

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/branches/4.2.x@1481339 13f79535-47bb-0310-9956-ffa450edef68