Add callout for OSS meetup (#446)

Signed-off-by: Dan Luhring <[email protected]>

README.md

@@ -8,6 +8,23 @@
 
 A CLI tool and go library for generating a Software Bill of Materials (SBOM) from container images and filesystems. Exceptional for vulnerability detection when used with a scanner tool like [Grype](https://github.com/anchore/grype).
 
+## Happening soon: [OSS Virtual Meetup](https://get.anchore.com/anchore-oss-meetup-jun-30-2021/)
+
+[**Register here!**](https://get.anchore.com/anchore-oss-meetup-jun-30-2021/)
+
+**When:** June 30, 11am-noon PT
+
+**What:** 3 fast-paced talks, with time for Q&A
+
+- **Using Syft to Streamline Compliance** (Chet Burgess — Principal Engineer, Cisco)
+
+
+- **Fast Container Scanning in CI: Three Ways to Use Grype in Your Builds** (Dan Luhring — Manager of Open Source Engineering, Anchore)
+
+
+- **Building More Optimal Container Images with Dive** (Alex Goodman — Creator of [Dive](https://github.com/wagoodman/dive), Sr Software Engineer for Open Source, Anchore)
+
+
 ![syft-demo](https://user-images.githubusercontent.com/590471/90277200-2a253000-de33-11ea-893f-32c219eea11a.gif)
 
 **Features**