Update README.md

Author: Alexey Kruchinin

README.md

@@ -64,7 +64,7 @@ Alternatively, from the command-line on Unix in the source directory:
 
     mkdir -p ../build/debug
     cd ../build/debug
-    cmake -DCMAKE_BUILD_TYPE=debug -DJSONCPP_LIB_BUILD_SHARED=OFF -G "Unix Makefiles" ../../jsoncpp-src
+    cmake -DCMAKE_BUILD_TYPE=debug -DJSONCPP_LIB_BUILD_SHARED=OFF -G "Unix Makefiles" ../../jsoncpp/src
     make
 
 Running `cmake -`" will display the list of available generators (passed using