Erroneous check if True

Originally checked for True as a string rather than a bool meaning that it would always default to running in non paranoid mode.

Pushover support (#10)

* Pushover support

* Update documentation to include setting up Pushover

Adds OSX support (#8)

* Adds OSX support

* Changes algorithm used to detect new devices

Add missing import for sanders-daemon

Python 3 compatibility (#5)

* (Preliminary support for Python 3 has recently been added)
* Python 3.6.1 --> 3.6
* print_function, function lookup
* print_function, save_settings() closes file
* Change to `with open` syntax, so the file is automatically closed.
* print_function, simplify identify_screensaver(), save_screensaver()

Merge branch 'master' of https://github.com/probablynotablog/usb-canary

Updated documentation and added contributing guide

public alpha release