Bug Fixes and optimisations as a result of issue 106

[steve-lad]

Fix bugs in Response Class causing exceptions Update extconfigs class to correctly check database connectors and improve feedback Move some constructors to start of class for lisibility Tidy up Response class with Typing to eliminate unnecessary tests

Issue 106 was due to Asterisk realtime connector errors, which caused exceptions that are resolved by this PR, and extension data in sccp.conf that should not have been there. Now handle correctly even if present.