Undo README changes

Author: ldionne

README.md

@@ -1,28 +1,24 @@
-LNT: LLVM "Nightly Test" Infrastructure
-=======================================
+LLVM "Nightly Test" Infrastructure
+==================================
 
-About
-=====
+This directory and its subdirectories contain the LLVM nightly test
+infrastructure. This is technically version "4.0" of the LLVM nightly test
+architecture.
 
-*LNT* is an infrastructure for performance testing. The software itself
-consists of two main parts, a web application for accessing and visualizing
-performance data, and command line utilities to allow users to generate and
-submit test results to the server.
+The infrastructure has the following layout:
 
-The package was originally written for use in testing LLVM compiler
-technologies, but is designed to be usable for the performance testing of any
-software.
+ $ROOT/lnt - Top-level Python 'lnt' module
 
+ $ROOT/lnt/server/db - Database schema, utilities, and examples of the LNT plist format.
 
-Documentation
-=============
+ $ROOT/docs - Sphinx documentation for LNT.
 
-The official *LNT* documentation is available online at:
-  https://llvm.org/docs/lnt
+ $ROOT/tests - Tests for the infrastructure.
 
+For more information, see the web documentation, or docs/.
 
-Source
-======
+Testing
+=======
 
-The *LNT* source is available in the llvm-lnt repository:
-  https://github.com/llvm/llvm-lnt
+Testing is done by running tox from the top-level directory. It runs the tests
+for Python 3 and checks code style.