Update resolvers/resolvers-httpcomponents-httpclient/src/main/java/org/codehaus/httpcache4j/resolver/HTTPClientResponseResolver.java

setEntity when content-length/teansfer encoding is set already crashes. 
RequestContent.process does not approve of this
Update resolvers/resolvers-httpcomponents-httpclient/src/main/java/org/codehaus/httpcache4j/resolver/HTTPClientResponseResolver.java

import 
Merge pull request #9 from hanskr/master

Avoid "org.apache.http.ProtocolException: Content-Length header already present" exception