Update download links for v1.8.0 (#993)

Author: kyleconroy

docs/overview/install.md

@@ -34,11 +34,11 @@ docker run --rm -v $(pwd):/src -w /src kjconroy/sqlc generate
 
 ## Downloads
 
-Get pre-built binaries for *v1.7.0*:
+Get pre-built binaries for *v1.8.0*:
 
-- [Linux](https://github.com/kyleconroy/sqlc/releases/download/v1.7.0/sqlc-v1.7.0-linux-amd64.tar.gz)
-- [macOS](https://github.com/kyleconroy/sqlc/releases/download/v1.7.0/sqlc-v1.7.0-darwin-amd64.zip)
-- [Windows (MySQL only)](https://github.com/kyleconroy/sqlc/releases/download/v1.7.0/sqlc-v1.7.0-windows-amd64.zip)
+- [Linux](https://github.com/kyleconroy/sqlc/releases/download/v1.8.0/sqlc-v1.8.0-linux-amd64.tar.gz)
+- [macOS](https://github.com/kyleconroy/sqlc/releases/download/v1.8.0/sqlc-v1.8.0-darwin-amd64.zip)
+- [Windows (MySQL only)](https://github.com/kyleconroy/sqlc/releases/download/v1.8.0/sqlc-v1.8.0-windows-amd64.zip)
 
 Binaries for a specific release can be downloaded on
 [GitHub](https://github.com/kyleconroy/sqlc/releases).