Make more user oriented sub classes

[daddabarba]

while the Socket class is very generic, some sub classes more user oriented can be created. eg:

• String socket (the handle and read functions reason in strings with starting and end charaters)
• JSON socket (the handle function parses the stream as a json first) (JSONCPP can be used for such purposes)

in the above examples, the user will still need to provide handling functions, which however are (under the hood ) piped to a parser of the data stream