More examples and tweaks

* Signal dispatch() method now uses own pid as default value
* SharedData now updates checksum cache on set()

composer.json

@@ -9,6 +9,12 @@
             "email": "cvagnetoft@gmail.com"
         }
     ],
+    "keywords": [
+        "ipc",
+        "shm",
+        "msgqueue",
+        "signals"
+    ],
     "require": {},
     "repositories": [
         {
@@ -24,4 +30,4 @@
             "NoccyLabs\\Ipc\\": "src/"
         }
     }
-}
+}