message: [README] move bazel stuff out of main README
diff: This repository contains various zk-SNARK protocol implementations for recursive SNARK composition.
  -Build all targets: `$ bazel build //...` (note: three dots)
  -
  -Note that the Zexe submodule is encoded as a Bazel workspace, so you
  -cannot build it directly by e.g. `bazel build //zexe/algebra`. Instead
  -you must use the Zexe workspace name: `baze build @zexe//algebra`.
  +## Bazel
  -## Bazel maintenance
  +Build all targets: `$ bazel build //...` (note: three dots)
  If you change any dependencies in the `Cargo.toml` files:
  