better readme

README.md

@@ -11,9 +11,12 @@ Build `cdec`:
 
 You will need the following libraries / tools:
 
-	boost
-	GNU Autotools
-	GNU Flex
+- [Autoconf / Automake / Libtool](http://www.gnu.org/software/autoconf/)
+    - Older versions of GNU autotools may not work properly.
+- [Boost C++ libraries (version 1.44 or later)](http://www.boost.org/)
+    - If you build your own boost, you _must install it_ using `bjam install`.
+    - Older versions of Boost _may_ work, but problems have been reported with command line option parsing on some platforms with older versions.
+- [GNU Flex](http://flex.sourceforge.net/)
 
 ## Further information