Add possibility to check current status

[moivica]

It would be nice to have some command that displays info about current options set so user can double check is everything prepared correctly before sending request.

eg
command: h2c check-options
output:

connection: 123.123.123.123 
headers: 
  <Header1> : <value1> 
  <Header2> : <value2> 
data:  {} 
....