improve basic readme

README.md

@@ -1,4 +1,19 @@
 # plethora
 
-Plethora is an HTTP performance testing command-line tool. It can generate very high numbers of concurrent connections
-HTTP performance testing command-line tool. Very high concurrency: can generate 1000s of simultaneous HTTP connections.
+Plethora is an HTTP performance testing command-line tool. It can generate
+very high numbers of concurrent connections (1000s).
+
+High concurrency is achieved using libevent.
+
+No SSL support at the moment.
+
+Please see the command-line help for usage instructions.
+
+
+Basic build instructions:
+
+1. install libevent
+2. ./buildconf
+3. ./configure
+4. make
+5. ./plethora -h