Added public files

Roughly added all public files. Probably missed some, though.
diff --git a/doc/concepts/simul_efun b/doc/concepts/simul_efun
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+CONCEPT
+        simul_efun
+
+DESCRIPTION
+        The simul_efun object is automagically sort-of inherited by
+        every object. That functions that are defined in it can be
+        accessed just like efuns or inherited functions by every
+        object (except the master object). To get access to efuns that
+        are overloaded by the simul_efun object, you can use the
+        efun::function() to bypass the simul_efun (unless the
+        simul_efun object has defined the function as ``nomask'').
+
+SEE ALSO
+        get_simul_efun(M), inheritance(LPC), operators(LPC)