Remove distinction between Intergovernmental Organization and Treaty Organization

[rjyounes]

According to Harvard Law School:

The term intergovernmental organization (IGO) refers to an entity created by treaty, involving two or more nations, to work in good faith, on issues of common interest. In the absence of a treaty an IGO does not exist in the legal sense. For example, the G8 is a group of eight nations that have annual economic and political summits. IGOs that are formed by treaties are more advantageous than a mere grouping of nations because they are subject to international law and have the ability to enter into enforceable agreements among themselves or with states...Among the oldest IGOs are the United Nations, which replaced the League of Nations, the Universal Postal Union, and the North Atlantic Treaty Organization (NATO).

Other sources agree:

Duke Law School: "International governmental organizations (or IGOs) are associations of states established by a treaty to pursue the common aims of their member states. An intergovernmental organization has a legal personality separate from its member states, and can enter into legally binding agreements with other IGOs or with other states. The United Nations and the Organization of American States are examples of international governmental organizations.
The other category of international organization is the non-governmental organization (or NGO). NGOs are made up of private citizens. NGOs do not enter into treaties or other international agreements. The World Wildlife Fund, Greenpeace and Amnesty International are examples of non-governmental organizations."

(Note the interesting distinction between IGOs and NGOs.)

Wikipedia: "An intergovernmental organization or intergovernmental organisation, also known as an international institution, is an organization composed primarily of sovereign states, or of other organizations through formal treaties for handling/serving common interests and governed by international laws."

(All emphases mine.)

It appears that "International Governmental Organization" is the most commonly used term, as opposed to "Treaty Organization."

[rjyounes]

Fix wtih #756.

[Jamie-SA]

If we remove "Treaty Organization" maybe add a altLabel on IntergovermentalOrganization of "Treaty Organization"?

[Jamie-SA]

DECISION:

• remove class TreatyOrganization
• Change prefLabel of IntergovernmentalOrganization to "Intergovernmental Organization". See Fix prefLabel of IntergovernmentalOrganization #756

[rjyounes]

Other to-dos:

• Add a regional example
• Update skos:definition to clarify that we mean to encompass both international organizations such as the UN and regional organizations such as the MTA.

[rjyounes]

@hmoore-sa Please include the fix for issue #756 in this PR.

[hmoore-sa]

Sorry for the delay- got busy and accidentally left this one off the radar. Will have the PR out at latest by the end of Monday, 10/17 with the following:

1. Deprecate TreatyOrganization in favor of parent class.
2. Update skos:Example of IntergovernmentalOrganization to "The United Nations, the European Union, the MTA (Metropolitan Transit Authority)"
3. Update skos:Definition to "An organization whose members are government organizations. This can comprise regional, municipal, state/province, or national level entities."
4. Changing prefLabel from: "Inter-Governmental Organization to "Intergovernmental Organization" (resolves 756).