Script crashes if used with non-text data on the clipboard

[acotis]

Kanakey crashes if you try to use it while your clipboard contains non-text data (such as image data). This is because the way it outputs the pretty Toaq text is that it copies the data to the clipboard and then simulates a "shift+insert" keypress in order to paste it. To avoid losing clipboard data, it first grabs whatever's on the clipboard, and then restores it afterwards (see the write_text() method in main.py). But it does so in a way that crashes if the data isn't text data. This might turn out to be an issue with the underlying Python library (clipboard).