Add link to custom validator doc in README

README.md

@@ -121,7 +121,7 @@ To run the schema validations, the command `schema-enforcer validate` can be run
 
 ```cli
 bash$ schema-enforcer validate
-schema-enforcer validate            
+schema-enforcer validate
 ALL SCHEMA VALIDATION CHECKS PASSED
 ```
 
@@ -140,12 +140,12 @@ If we modify one of the addresses in the `chi-beijing-rt1/dns.yml` file so that
 
 ```cli
 bash$ cat chi-beijing-rt1/dns.yml
-# jsonschema: schemas/dns_servers       
+# jsonschema: schemas/dns_servers
 ---
 dns_servers:
   - address: true
   - address: "10.2.2.2"
-bash$ test-schema validate            
+bash$ test-schema validate
 FAIL | [ERROR] True is not of type 'string' [FILE] ./chi-beijing-rt1/dns.yml [PROPERTY] dns_servers:0:address
 bash$ echo $?
 1
@@ -161,3 +161,4 @@ More detailed documentation can be found inside of README.md files inside of the
 - [The `validate` command](docs/validate_command.md)
 - [The `schema` command](docs/schema_command.md)
 - [The Ansible command](docs/ansible_command.md)
+- [Creating custom validators](docs/custom_validators.md)