Fix strtoul 'endptr' return value: It should point to the first invalid character,
not to the last valid character.
testcode/lib/tinyshell.c: add 'verbose' and 'cls' commands; add SP check
testcode/lib/tinyshell.c: fix error message
testcode/lib/tinyshell.c: Enable SP check only for CC65
targets. Enable 'cls' command only for Atari. Enable subdirectory
commands only for Atari and non-CC65 targets.
Fix strtol 'endptr' return value.
Fix last change: Stack check for all CC65 targets. Enable subdirectories on Apple 2.
Merge pull request #39 from groessler/something_to_pull

Fix strtoul 'endptr' return value: It should point to the first invalid character,
Merge pull request #40 from groessler/something_to_pull2

testcode/lib/tinyshell.c: add 'verbose' and 'cls' commands; add SP check
Remove obsolete ZPSAVE segment.
Merge pull request #41 from groessler/something_to_pull

Remove obsolete ZPSAVE segment.
add IOCB command codes to atari.h
add testprogram for _sys() function on Atari
Merge pull request #42 from groessler/something_to_pull

Testprogram for _sys() on Atari; some atari.h changes
override _sys() function for Atari targets
use '.ifndef' instead of '.if .not .defined'
Merge pull request #43 from groessler/something_to_pull

override _sys() function for Atari targets