for conversions.m2

new Matrix from List := (Matrix,v) -> matrix v

    -- This one will not work currently, because:
    --     (1) Matrix is a type of HashTable
    --     (2) there is already a (built-in) method for new HashTable from List
    --     (3) the internal code uses the method for new HashTable from List
    -- I'll fix that in the engine eventually.

