Add missing include statements, add missing "static" qualifiers or
remove functions which are not used at all.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Tesseract code does not use strings.h (strngs.h was once called strings.h),
so that dependency can also be removed from cmake and cppan configuration.
Signed-off-by: Stefan Weil <sw@weilnetz.de>