Ket TM-sequence-hash input-seq
hashes the given input sequence into a relatively collision free, deterministic, hash
the input-seq must be a sequence of kets, not superpositions
and any coeffs of those kets will be ignored
if superpositions are required then pre-process with tensor-product
if the input seq is empty, it returns the empty ket
this operator is a member of the Template Machine set of operators
we may later swap to returning a hex-string instead of decimal
mostly deprecated by TM-ket-hash