Updates to Timelord.md

BUILD_TIMELORD.md

@@ -0,0 +1,27 @@
+The Linux and MacOS chiavdf binary wheels currently exclude an executable
+required to run a Timelord. If you want to run a Timelord on Linux or MacOS,
+you must install the wheel from source (which may require some additional
+development packages) while in the virtual environment.
+
+```
+. ./activate
+
+sh install-timelord.sh
+```
+
+If the compile fails, it's likely due to a missing dependency.
+[install-timelord.sh](https://github.com/Chia-Network/chia-blockchain/blob/master/install-timelord.sh)
+attempts to install required build dependencies for Linux and MacOS before
+invoking pip to build from the source python distribution of chiavdf.
+
+The `install-timelord.sh` install script leverages two environmental variables
+that the chiavdf wheels can use to specify how to build. `vdf_client` is the
+service that the Timelord uses to run the VDF and prove the Proof of Time.
+`vdf_bench` is a utility to get a sense of a given CPU's iterations per second.
+
+- To build vdf_client set the environment variable BUILD_VDF_CLIENT to "Y".
+`export BUILD_VDF_CLIENT=Y`.
+- Similarly, to build vdf_bench set the environment variable BUILD_VDF_BENCH
+to "Y". `export BUILD_VDF_BENCH=Y`.
+
+Building and running Timelords in Windows x86-64 is not yet supported.