calc 2.12.7.0 release

The following are the changes in this release:

Added a patch to replaces the manual search for include files
in $(INCDIR) in the have_*.h targets with compiler invocations.
Thanks goes to Helmut Grohne (helmut at subdivi dot de) who
implemented the patch and posted it to the Debian bug tracker
and Martin Buck (m at rtin-buck dor de) for forwarding it to us.

The check_include make rule was fixed to not assume /usr/include.

The qprintnum() function now takes outdigits as a 3rd argument.
Most of the time, this 3rd argument is just conf->outdigits.
But when it comes to the experimental '%g', this value can
change.  This avoids having to modify conf->outdigits.

Fixed a problem where gcc complains about E_FUNC not being defined
for Linux systems as reported by Martin Buck (m at rtin-buck dor de).

Updated the help files help/config, help/display, help/epsilon,
help/fprint, help/printf, and help/strprintf to give more
examples of how display digits and epsilon precision interact
with displaying values.

Added more information about %g in the help file help/printf.

The '\a' is now recognized in a printf format string as the
single byte audible bell character (byte 0x07 in ASCII encoding).

The following is a partial list of escape sequences recognized
in strings and in printf formats:

\a	audible bell	byte 0x07 in ASCII encoding
\b	backspace	byte 0x08 in ASCII encoding
\f	form feed	byte 0x0c in ASCII encoding
\n	newline		byte 0x0b in ASCII encoding
\r	return		byte 0x0a in ASCII encoding
\t	tab		byte 0x0d in ASCII encoding
\v	vertical tab	byte 0x09 in ASCII encoding