Changes:
* The documentation file doc/install.txt has been improved to describe
the command 'make install'.
* The chapter about the foreign function interface in the manual has
been improved.
* In striutl.h the macros os_stri_alloc and os_stri_free have been
improved to use a stack like allocation. Allocations done with
os_stri_alloc must be freed with os_stri_free in the reverse order
of their creation. The new macros reduce the runtime of
stri_to_os_stri and cp_to_os_path to 66% of the old time. This
reduces the time used by operating system calls. E.g.: The CPU time
used by the program sydir7 is reduced to 83% of the old time.
* The targets 'install' and 'uninstall' have been added to makefile,
mk_linux.mak, mk_osx.mak, mk_clang.mak, mk_cygw.mak, mk_mingw.mak,
mk_msys.mak, mk_nmake.mak, mk_msvc.mak, mk_bcc32.mak and
mk_bccv5.mak.
* The program setwpath.c has been added. This program sets the search
path (PATH variable) under Windows.
* The obsolete target 'hi' has been removed from the makefiles.
* The functions initEmulatedCwd, cmdSetenv (both in cmd_rtl.c),
setEmulatedCwd (in striutl.c) and freeArgVector (in cmd_unx.c) have
been adjusted to work with the stack like allocation of
os_stri_alloc and os_stri_free.
* The functions heapAllocOsStri and heapFreeOsStri have been added to
striutl.c.
* Usages of MAX_SYMLINK_PATH_LENGTH in cmd_rtl.c have been replaced
with MAX_OS_STRI_LEN.