add get_mse_path script function

doc/function/get_mse_path.txt

@@ -0,0 +1,6 @@
+Function: get_mse_path
+
+--Usage--
+> get_mse_path()
+
+Returns the current MSE app folder absolute path.

doc/function/index.txt

@@ -113,6 +113,7 @@ These functions are built into the program, other [[type:function]]s can be defi
 	
 ! Other functions		<<<
 | [[fun:get_mse_version]]			Get the MSE app version.
+| [[fun:get_mse_path]]			Get the MSE app folder absolute path.
 | [[fun:trace]]			Output a message for debugging purposes.
 | [[fun:assert]]		Check a condition for debugging purposes.
 | [[fun:warning]]		Output a warning message.