Add brainstorm note about player safety

BRAINSTORM.txt

@@ -1,3 +1,11 @@
+- some conditiosn you cannot attack someone in
+    * theyre in combat already
+    * theyre in a safe area
+    * theyre not within your power level range, idk if that is 5-10%, and
+      i mean potential PL. no powering down games, thatd let you destroy brand
+      new players
+    * brand new players have a safe window of say, 1 hour play time
+
 - i think maybe the world is cleaned up by both animals and janitors
 
 - look <object>