Fix hyperspy compatibility and numpy deprecation warning

[ericpre]

• [x] Fix numpy deprecation warning, see https://numpy.org/devdocs/release/1.20.0-notes.html#deprecations
• [x] validate input using np.asanyarray to fix the issue describe in https://github.com/usnistgov/pyMCR/pull/33#issuecomment-688884855

[ericpre]

@CCampJr, could you please review this PR and merge it if possible?

[CCampJr]

@ericpre Apologies for the delay -- thanks for your efforts!