poly2sym from the original octave-symbolic pkg

thanks to Willem J. Atsma <watsma@users.sf.net>
no vpa stuff for poly2sym
move poly2sym(l, x) version to @sym
record where bug 17 has been worked around (subsref instead of ())
poly2sym: add tests and use m*tl*b compatible code
findsym from the original octave-symbolic pkg

thanks to Willem J. Atsma <watsma@users.sf.net>
sort in findsymbols fails on sympy 0.7.5 :(
workaround upstream SymPy bug #7413
findsym oct style to matlab, more tests

some extra trimming as my disp() has leading whitespace
sym2poly, originally by Willem J. Atsma <watsma@users.sf.net>

I rewrote the body to use SymPy but kept comment header, and tests

Also added more tests
reformat comments to have lookfor line, also wip edits to poly2sym
poly2sym: switch to monomial form, update comments
horner.m added
simplify
Merge branch 'findsym'

incorporate some code from octave-symbolic project, GPL-3, attributed to Willem J. Atsma <watsma@users.sf.net>

implement a few other things on that branch too
Fix Bug #16: a script to run the embedded octave tests

Also, fix the other script to not have variables called "test" (which would break the new script)
quiet tests that won't pass until we have Bug #14
more files around for octave package
DESCRIPTION file
move unit tests too