Optimise S-Save if deferd and binary or none of dos or tab or fm-s,+l &c
Retire separate MACRO & HELP directories
STARTED: README_DEBUG_ALU (was to be README_DEBUG_ADVANCED) to describe
	how to debug ALU programs and have table of useful variables
	ptrpos, tabs rs[], fs[], rsidx, fsidx, xreg, qreg
	curr, prev, oldcom, newcom
Mode to turn off line & part numbering (entire line selectable on V or P)
Opcodes POPL & POPLF: pop to line being edited (command or file)
Q -B to break long lines on token delimiter if length so far > 32(?)K
Give symbolic names to ALU memory locations e.g. fs,0,i^J^<POP i>
 Error if try to rename location
 Error if use same name twice
command-line option to insert "fm +l" command before reading file
Search up directory tree for .qrc
Use .qrc associated with file to edit
ALU is always 64-bit (required for > 32 mode bits)
cater for >4G lines in L & Y
Give some kind of acknowledgement to ^NF (& ^NO?)
-H option to give invocation help
Can set actual amount for "1 line forward / back" half-page / full-page
Properly reinstate output optimisation (old hack removed as "quick fix")
 use ioctl TIOCOUTQ to get # chars waiting to go
 needs select() /poll() and/or ioctl FIONREAD
 needs nanosleep when outputting chars
 get per-char delay from stty baud rate
 reinstate setting per-char delay (useful for testing)
INTERNALS
	scrdtk to be 64-bit on 64-bit systems
Show what arguments Q started with (?)
STARTED: Catalogue of useful macros
New pseudomacro to replace "/*" with arbitrary seq: #, // &c (i.e. for ^O)
New pseudomacro to be obeyed on q <filename>
	default ^NU, may be re-defined (e.g. to ^N^W^X)
^T in a macro to action pending ^C (like ^J does)
Pass on SIGWINCH (to e.g. !less)
