Release Amalgamate version 0.1.46.
Release Amalgamate version 0.1.46.

 * Upgrade `skip` to `0.2.28`.
 * Upgrade `b-tree` to `2.0.0-alpha.89`.
 * Upgrade `splice` to `3.0.0-alpha.48`.
 * Upgrade `riffle` to `2.0.0-alpha.64`.

Closes #215.

bigeasy/amalgamate,bigeasy/amalgamate