speculator allows you to preview pull requests to the matrix.org specification.

It serves the following HTTP endpoints:
 - / lists open pull requests
 - /spec/123 which renders the spec as html at pull request 123.
 - /diff/rst/123 which gives a diff of the spec's rst at pull request 123.
 - /diff/html/123 which gives a diff of the spec's HTML at pull request 123.

The build or run, you need a working `go` installation.
Then fetch dependencies:
 ` go get github.com/hashicorp/golang-lru`

To run it, then run:
 `go run main.go`

To build the binary (which is necessary for deployment to the matrix.org
servers), you must again install `go` and dependencies, and then run:
 `go build`