Release-independent core for the FHIR crates.
Everything here is the same for R3, R4, and R5: one Decimal, one
Validate trait, one Coded<E>, one date/time parser, one XML reader,
one REST client generic over [release::Release]. The release crates
depend on this one and re-export its items under their own paths, so
fhir::r5::validate::Validate and fhir::r4::validate::Validate are the
same trait and a value from either release satisfies it.
That sharing is the point. A Validate defined per release would make
impl Validate for T non-portable across releases, and a Decimal
generated three times would be three incompatible types for one FHIR
primitive.
This crate is not intended to be depended on directly; use fhir.