Examples of external objects for Pd.

Here are the sources for a few simple external objects in Pd, along with patches
to test them.  There is a makefile included that should help compile them
using the "make" (Mac or linux) or "nmake" (Windows) shell commands.

This relies on having installed a development environment for whatever computer
is in use.  For Windows, this should be Microsoft Visual C (it's also possible
to compile externs using mingw but this makefile doesn't support that).

To compile, type "make pd_linux", "nmake pd_nt" (for windows), or
"make pd_darwin" (for Mac OSX).

If you have saved these files to a new location (other than the Pd distrubution
itself), it will probably be necessary to customize the makefile by changing the
definition of "PDNTINCLUDE" (windows) or "LINUXINCLUDE" (linux or Mac)
to point back to the PD source directory.

Mac users who haven't installed a 32-bit compilation chain will also have to
edit the makefile to delete the phrase "-arch i386" in two places.

Windows users will most likely have to update the makefile to point correctly to
the current version of Microsoft Visual C.
