Process all substrates in Composite Material Tables

[sanjeetsuhag]

From the OGC CDB Core Standard: Model and Physical Data Store Structure, Page 53:

2.5.2.2 Composite Material Tables (CMT)

Composite Material Tables provide the means by which Composite Materials can be defined.
Each entry within a Composite Material Table defines a structured arrangement of basic
materials or of aggregates (i.e., a Composite Material). Each Composite Material entry is
assigned a Composite Material Index (and an optional name). CDB datasets can then make use
of the index value in order to select Composite Materials.

There are several Composite Material Tables spread across the CDB hierarchy. Note however
that all Composite Material Tables follow a common XML notation that describes each
Composite Material into its primary substrate, surface and secondary substrate components.
Composite Materials Tables can take various forms, either as distinct XML files or embedded
XML code within a file.

The XML encoding is as follows:

Currently, this pipeline only supports processing and storing the Primary Substrate. When data is made available that has Composite Materials with the Surface and Secondary Substrate(s), we should add support for processing those properties. It should be trivial to add to the pipeline. These properties, along with the Thickness property for each substrate, should be optional in EXT_feature_metadata.