updated install

INSTALL

@@ -4,11 +4,16 @@ Requirements (copied from clingo)
 - a c++11 conforming compiler
     gcc version 5.2 (earlier versions will not work)
     other compilers might work
-- clingo 5.0 sourcecode,
+- clingo 5.0.0 sourcecode,
     to be put into the clingo folder
     if you received this code via git clone, just call
     git submodule init
     git submodule update
+- libcsp 1.0.0 sourcecode,
+    to be put into the libcsp folder
+    if you received this code via git clone, just call
+    git submodule init
+    git submodule update
 - the bison parser generator
     version 3.0 is tested (produces warnings to stay backwards-compatible)
     version 2.5 and newer should work (earlier versions will not work)