Unbind click events before binding new
Fix image request so not to request ever longer strings
Default to 205mm print bed, same as Cura
Port web interface to web.py

This is the first part of porting the web interface to FastCGI in order to
increase performance by reducing process creation overhead.
Alter lighttpd config to switch from cgi to fastcgi
Add python-webpy and python-flup packages
Reinstate use of nice-python on web app
Prefer relative URLs
Add jquery form plugin

Will be used for file uploads.
Minor fix to status image HTML
Add gcode upload form using jquery form plugin
Add backend handling of gcode uploads