split functionality to additional classes
Config - configuration
Connector - connection objects cache and helpers
Data - shared data
BtCP - 'copy' object, representing a single file transfer
major refactoring, unstable

moved some functionality into additional classes:
  * data
  * connector
  * web
refactored the following classes:
  * btcp - now serves as an instance of copy
  * flowcontrol - a control of all copies