[PD] Obscure pd externals in search path shadow .pd files in current working directory

[Julius Smith]

Hi All,

In figuring out why seqdemo.pd did not work (in the cool
faust/tools/faust2pd/examples distribution), I discovered that the local
file ./seq.pd was being shadowed
by /usr/lib/pd/extra/cyclone/seq.pd_linux.  It appears that, due to
search order, all externals, wherever they may reside in the search
path, take precedence over .pd files, even those in the current working
directory.  It seems to me both externals and subpatches in the cwd
should take precedence over the rest of the search path. Also, I would
expect subpatches to take precedence over externals in the same
directory (with a warning about the shadowing printed to the console).

My workaround, by the way, was to rename seq.pd to seqr. pd in the
seqdemo directory. 

Cheers,
Julius