Plain TCP connection handler.
Added connection timeout.
Merge pull request #32 from rafalwrzeszcz/feature/tcp-connection

Abstract connection and add plain TCP connection handler.
Remove doc/api directory.
Declare request timeout on AbstractConnection
and implement it in both connection types.
Update docs

add setTimeout method and responseHeaders field
Fix some Namespacing issues
Release v3.2.0
doc/tutorial: Document HttpConnection#setHeader modifier