patch `elftoc' to use signed chars where appropriate;
plain char can be unsigned as well as signed (it is implementation-dependent);
discovered by compilation warning:
    outbase.c:226:6: warning: comparison is always true due to limited range of data type [-Wtype-limits]
    if (i < length - 1 && str[i + 1] >= 0 && str[i + 1] <= 7)
                          ^
modified: elftoc/outbase.h, elftoc/outbase.c, elftoc/out.c
for ELF version check in header, use EI_VERSION, but not EI_DATA
fixed stupid but harmless bug in outbase.c; improved comments while at it
Merge branch 'master' of https://github.com/dougmencken/ELFkickers into dougmencken-master
removed bad part of fix from merge