Add links to OpenSSF Vulnerabilities Disclosures WG (#119)

We always want projects/SIGs to point to their working group, but this
one doesn't. Let's fix that, and tweak some other text along the way so
it's clearer for visitors.

Signed-off-by: David A. Wheeler <dwheeler@dwheeler.com>
Signed-off-by: Oliver Chang <oliverchang@users.noreply.github.com>
Co-authored-by: Oliver Chang <oliverchang@users.noreply.github.com>

README.md

@@ -1,6 +1,6 @@
 # Open Source Vulnerability Schema
 
-This is the repository for the Open Source Vulnerability schema, which is currently exported by:
+This is the repository for the Open Source Vulnerability schema (OSV-schema), which is currently exported by:
 - [GitHub Security Advisories](https://github.com/github/advisory-database)
 - [PyPI Advisory Database](https://github.com/pypa/advisory-database)
 - [Go Vulnerability Database](https://github.com/golang/vulndb)
@@ -43,8 +43,10 @@ Together, these include vulnerabilities from:
 -   Rocky Linux
 -   RubyGems
 
-These vulnerabilities are aggregated by https://osv.dev.
+These vulnerabilites are aggregated by <https://osv.dev>.
 
 Reference tooling (e.g. converters) can be found in the [tools/](tools) directory
 
-The current version of spec is rendered [here](https://ossf.github.io/osv-schema/).
+The current version of the specification is rendered [here](https://ossf.github.io/osv-schema/).
+
+The OSV-Schema specification and the tools here are maintained by the [Open Source Security Foundation (OpenSSF)](https://openssf.org/) [Vulnerability Disclosures Working Group (WG)](https://github.com/ossf/wg-vulnerability-disclosures).