Document how to reference REST enabled SQL

[martindsouza]

This is dependant on updates to martindsouza/docker-oracle-ords#10

Key here is that the URL that you use is from within the Docker network. Ex: my current REST enabled SQL (while referencing from my laptop) is: http://localhost:32181/ords/giffy/_/sql but when defining this as a REST Enabled SQL End Point in APEX 18.1 on a Docker network it's: http://ords-1810:8080/ords/giffy where ords-1810 is the name of my ORDS docker container and 8080 is it's native port

Note: I know it doesn't make sense for the DB to "query itself" over REST for performance reasons. Usecases are:

• Testing out the REST enabled SQL
  • For both APEX data source and also from curl (or other RESTful apps)
• Connecting to other PDBs
• Perhaps even connecting to other Oracle DBs on the same Docker network (low probability given the purpose of this project)