It is now possible to create a Point from a constant.
This functionality is required to evaluate the old nullifier.
- for non split_notes, nf_old = Extract_P([PRF^{nfOrchard}_{nk}(rho_old) + psi_nf) mod q_P] NullifierK + cm_old)
- for split notes, nf_old = Extract_P([PRF^{nfOrchard}_{nk}(rho_old) + psi_nf) mod q_P] NullifierK + cm_old + NullifierL)

Short range checks on 4 and 5 bits are now performed with only one lookup (instead of 2).
To do that, we added a column `table_short_range_tag` in the lookup table.
This new column `table_short_range_tag` contains the value
- 4 for rows used in short range check on 4 bits
- 5 for rows used in short range check on 5 bits
- 0 for rows used in short range check on 10 bits

Disable tests on i686 and code coverage in CI

It is now possible to perform a mux between two points or between two non-identity points.
`mux(choice, left, right)` will return `left` when `choice=0` and `right` when `choice=1`.
`choice` must be constrained to `{0, 1}` outside the gate.

It is no longer needed to expose `from_coordinates_unchecked`.

…oint (#22)

To share ZEC and ZSA hash computations in Orchard circuit's note commitment evaluation, we need to compute a Sinsemille hash from a private input point.