Implement builtins

[sandhose]

• [x] base64url.encode_no_pad
• [x] crypto.hmac.md5
• [x] crypto.hmac.sha1
• [x] crypto.hmac.sha256
• [x] crypto.hmac.sha512
• [x] crypto.md5
• [x] crypto.sha1
• [x] crypto.sha256
• [ ] crypto.x509.parse_and_verify_certificates
• [ ] crypto.x509.parse_certificate_request
• [ ] crypto.x509.parse_certificates
• [ ] crypto.x509.parse_rsa_private_key
• [ ] glob.quote_meta
• [ ] graph.reachable_paths
• [ ] graphql.is_valid
• [ ] graphql.parse
• [ ] graphql.parse_and_verify
• [ ] graphql.parse_query
• [ ] graphql.parse_schema
• [x] hex.decode
• [x] hex.encode
• [ ] http.send
• [ ] indexof_n
• [ ] io.jwt.decode
• [ ] io.jwt.decode_verify
• [ ] io.jwt.encode_sign
• [ ] io.jwt.encode_sign_raw
• [ ] io.jwt.verify_es256
• [ ] io.jwt.verify_es384
• [ ] io.jwt.verify_es512
• [ ] io.jwt.verify_hs256
• [ ] io.jwt.verify_hs384
• [ ] io.jwt.verify_hs512
• [ ] io.jwt.verify_ps256
• [ ] io.jwt.verify_ps384
• [ ] io.jwt.verify_ps512
• [ ] io.jwt.verify_rs256
• [ ] io.jwt.verify_rs384
• [ ] io.jwt.verify_rs512
• [x] json.patch
• [ ] net.cidr_contains_matches
• [ ] net.cidr_expand
• [ ] net.cidr_merge
• [ ] net.lookup_ip_addr
• [ ] object.union_n
• [x] opa.runtime
• [x] rand.intn
• [ ] regex.find_n
• [ ] regex.globs_match
• [ ] regex.split
• [ ] regex.template_match
• [ ] rego.parse_module
• [x] semver.compare
• [x] semver.is_valid
• [x] sprintf
• [x] time.add_date
• [x] time.clock
• [x] time.date
• [ ] time.diff
• [x] time.now_ns
• [x] time.parse_duration_ns
• [ ] time.parse_ns
• [x] time.parse_rfc3339_ns
• [x] time.weekday
• [ ] trace
• [x] units.parse
• [x] units.parse_bytes
• [x] urlquery.decode
• [x] urlquery.decode_object
• [x] urlquery.encode
• [x] urlquery.encode_object
• [ ] uuid.rfc4122
• [ ] yaml.is_valid
• [ ] yaml.marshal
• [ ] yaml.unmarshal

[kaplanelad]

Hey @sandhose you can marked as done the following builtins? yaml.-> PR: #44 object.union_n -> PR: #135 (waiting for review) regex. -> PR: #128 (waiting for review)