Added almost instant pause functonality
Support pause and resume macros
Support nested macros
Support zpl's web interface
Merge in zpl's web interface and network changes
Add R parameter to M105 command for PanelDue
M98 can now run macros from any SD card folder
Added support for nozzle offsets in G10 command
Disable heater timeout if the time limit is set to zero or negative
Don't send non-error responses to the web interface unless the
corresponding command also came from the web interface
Added support for aux input from serial. Need to finish this by making
serial transmission interrupt-driven.
Incoming network requests can now span multiple TCP messages. Max upload
buffer increased to 2048. Also return layerHeight and generatedBy values
when asking for fileinfo on a gcode file. This is an interim commit that
needs cleaning up before release.
