Most files already used spaces, but three used tabs for indentation. These have been converted to use spaces. This allows the files to be displayed with proper formatting in modern editors and on GitHub. It also removes any dependency on SysTabs settings when assembling them.
The spacing in fpextra.asm was also modified to use standard column positions.
There are no non-whitespace changes in this commit.
If the upper byte of the int argument was nonzero, it could write the wrong value (the OR of the upper and lower bytes). It should convert the value to unsigned char, i.e. just use the lower byte.
Tabs have been expanded to spaces in several files that use mainly spaces for indentation.
The files ctype.asm, stdio.asm, and string.asm consistently use tabs for indentation. The tabs in these files have been left alone, except that a few tabs between sentences in comments were changed to spaces. One space-indented line in stdio.asm was changed to use a tab.
It had been doing a null pointer dereference and effectively treating memory locations starting from 0 as the continuation of the string, potentially producing inappropriate results depending on what they contained.
