Fixed pip installation from Anaconda; minor updates

• fixed CK execution with Anaconda python (Linux and MacOS) when installed via pip:
  pip install ck
  or
  pip install ck --user
• improved OpenME to call CK in dynamic websites
• added passing of $_SESSION, $_POST, $_GET to CK via OpenME
• added "Access-Control-Allow-Origin=*" to module:web to be able to access CK from local web pages
• added possibility to change default repo using "CK_DEFAULT_REPO" env var
• added flag --module_version to use different Python module (module{.{module_version}}.py)