improved docs in the GeneralName class [ci skip]
some helper methods in the R509 module itself
expand config validation checks, improve readme
remove hmac support (it'll appear in another gem)
support passing nil to R509::ASN1.general_name_parser
small validation point on cdp_location
modify CertificateAuthority::Signer to support multiple GeneralName

types in cdp_location, ocsp_location, and ca_issuers location. The types
are auto-parsed using R509::ASN.general_name_parser (just like we do
in R509::CSR and other places)
modify authorityKeyIdentifier to no longer encode the issuer since
that's not a thing most "real" CAs do
add support for inhibitAnyPolicy and policyConstraints in issuance

this means adding it to the YAML configs, the validators in CAProfile,
altering CertificateAuthority::Signer, and updating the README
name constraints signing support. phew.
(very) basic test to check if name_constraints are loaded from yaml
refactor GeneralName, GeneralNames#create_item, and the

general_name_parser to allow unencoded data in a...less lousy way
change the error type when passing a CSR to the Cert object.

formerly an R509Error, now an ArgumentError
fix some documentation errors [ci skip]
doc fix [ci skip]
some basic test additions to Cert to verify return types