Better catch bad arguments to mxMatrix
Better catch bad arguments to mxMatrix

Resolves #202

> require(OpenMx)
Loading required package: OpenMx
Notice: R GUI cannot display verbose output from the OpenMx backend. If
you need detail diagnostics then R CMD BATCH is one option.
> mxMatrix(name="parameters", 1, 1)
Error in match.barg(as.character(type), choices = matrixTypes) :
  '1' should be one of 'Diag', 'Full', 'Iden', 'Lower', 'Stand',
'Sdiag', 'Symm', 'Unit', and 'Zero'
>

jpritikin/OpenMx,jpritikin/OpenMx,jpritikin/OpenMx,jpritikin/OpenMx,jpritikin/OpenMx,jpritikin/OpenMx