Enabled usage of Key Names instead of key codes in configuration file. 

This required the external keysym(https://github.com/substack/node-keysym) library. 

Symbols are not detected, actual Key Names are required. As an example: a semicolon should be specified as `semicolon` and not as `;`. Key Names can be found in the KeySyms specification at:
http://www.cl.cam.ac.uk/~mgk25/ucs/keysyms.txt