SEC-175 - Augment the definition of an ADR to describe Chinese ADRs

[ElisaKendall]

Signed-off-by: Elisa Kendall ekendall@thematix.com

Description

1. Added the concept of a variable interest entity (VIE) to legal entities and of a VIE share to equity instruments, required to define a Chinese DR
2. Added the concept of a generic Chinese DR without necessarily tying it to a VIE, but now those kinds of CDRs can be represented as appropriate

Fixes: #1838 / SEC-175

Checklist:

• [x] I'm familiar with the FIBO developer quide. My contribution meets all the requirements described there.
• [x] My contribution follows the principles of best practices for FIBO.
• [x] My changes have been reconciled with latest master and no merge conflicts remain.
• [x] This PR is related to exactly one issue. The issue is referenced by using a GitHub keyword such as "fixes", "closes", or "resolves".
• [x] Hygiene tests have been applied by a PR with "(WIP)" in title.
• [x] The issue has been tested locally using a reasoner (for ontology changes).