added pill to roboNurse grammar

ps-grammar/roboNurse/roboNurse.jsgf

+#JSGF V1.0;
+grammar roboNurse;
+
+public <root> = [tobi] [please] (<command>);
+<command> = (<assistance>|<pills>|<pillsspec>);
+
+<assistance> = [i need] [your] assistance;
+<pills> = [i need] [my] (pills|pill);
+<pillsspec> = [i need] [the] <properties> (one|bottle);
+
+<properties> = (leftmost|rightmost|blue|red|green|big|small);