Use the hasItems matcher instead of is to match a list, avoiding ordering problems

Signed-off-by: John May <john.wilkinsonmay@gmail.com>
Added 2 additional tests for MassToFormulaTool and
MolecularFormulaGenerator

Signed-off-by: John May <john.wilkinsonmay@gmail.com>
Minor code cleanup

Signed-off-by: John May <john.wilkinsonmay@gmail.com>
Ignore deficiency tests in the old MassToFormulaTool.
Updates to README.