MCH schema and documentation

[isedwards]

• [x] Prepare an empty SQL dump of a default MCH database and upload to the /cdms/mch/v1/ directory in this repository
• [ ] Also add any relevant documentation that describes how the data model is used in /cdms/mch/v1/docs/

(Replace v1 with a version number to identify the database at this point in time)

This issue relates to the work plan discussed during the May 2019 collaboration meeting in Reading:

Who	Task
MCH	To document MCH database for the OpenCDMS team
MCH	To build a first version of the data model from a script specification (tool: PostGIS)

[eporrasc]

The script is sent to create the initial MCH database

Create_MCH_English_basic_tables.zip