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
Fixed bug: if 5 point bed compansation was used then doing G32 more than
once would try to move the head off the edge of the bed unless the first
4 probe coordinates were reset between them.
Fixed bug: if the last command in a a macro file did not end in newline
then it might not be fully executed
Bug fix: potential array underrun in Gcodes::Pop()
Reduced Z dive height back to 5mm
