StringUtils: added containsIgnoreCase
StreamValidEOF: helper interface for EOF validation
ChunkedInputStream: implemented StreamValidEOF
LimitedInputStream: implemented StreamValidEOF
HTTPConnectionImpl:
-added keep-Alive support in 3 different modes
-1.) DISABLED = no keep-alive support
-2.) ENABLED_INTERNAL = only works for GET/HEAD/OPTIONS/DELETE, as the retry happens within connect
-3.) EXTERNAL_EXCEPTION = retry happens externally, also supports POST/PUT
SocksHTTPconnection: fixed sync issues
HTTPKeepAliveSocket: helper class to keep-Alive handling in HTTPConnectionImpl
HTTPProxyHTTPConnectionImpl/SocksHTTPconnection: no keep-Alive support yet

git-svn-id: svn://svn.appwork.org/utils@2076 21714237-3853-44ef-a1f0-ef8f03a7d1fe
git-svn-id: svn://svn.appwork.org/utils@2077 21714237-3853-44ef-a1f0-ef8f03a7d1fe