adding documentation to README

test/README.md

@@ -1,2 +1,11 @@
-CAVEAT: set environment variable HOME to a test directory before executing these tests!
+= Tests in this directory =
+
+$ HOME=$PWD python3 basic_doctest.py -v
+    do some basic tests of p≡p
+
+    CAVEAT: set environment variable HOME to a test directory before executing
+    this test
+
+$ python3 sync_test.py
+    start two processes representing two devices and do a sync test