fix-r2009a

Compatibility fixes for R2009a.  Mostly, this is just a lot of replacing tildes used to ignore return values with dummy variables.  All tests are passing for me in both R2009a and R2013b except for `tests/fun/test_detectEdge.m`, which is failing in R2009a due to #809 and which can easily be made to fail on development in R2013b just by changing the number used to seed the RNG.

This closes #422.