Permit use of _$ as a capture-of-wild - terser than _$()
Rename requal to matcherEquals
Sundry set API renamings and additions
Improved pretty-printing of matchers
Gestalt equality; also export matcherEquals
.smallerOf and .largerOf were buggy; remove them
Eventually we should support Infinity as a level number.
Default to 0 for simpleGestalt metaLevel and level
Split out function gestaltUnion
In browsers, export more carefully