M0-M1 Enhancements

Allow M0 and M1 to include a message string. Ignore clicks on “Wait for
user” so that the Info Screen stays up.
Relocate click ignore code into info screen
Clear LCD to welcome_msg if not printing

The welcome message is more appropriate than “resuming print” if
nothing is printing.
Ignore S and P if no value >0 is included.
get latest Marlin_v1 changes
M0-M1 Enhancements

Allow M0 and M1 to include a message string. Ignore clicks on “Wait for
user” so that the Info Screen stays up.
Relocate click ignore code into info screen
Clear LCD to welcome_msg if not printing

The welcome message is more appropriate than “resuming print” if
nothing is printing.
Ignore S and P if no value >0 is included.
get latest Marlin_v1 changes
Merge branch 'lcd_wait_better' of https://github.com/thinkyhead/Marlin into lcd_wait_better
kill DEADJOE
Merge pull request #1155 from thinkyhead/lcd_wait_better

M0-M1 Enhancements