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.

src/script/functions/basic.cpp

@@ -19,6 +19,9 @@
 #include <data/card.hpp>
 #include <data/game.hpp>
 #include <random>
+#include <wx/filename.h>
+#include <wx/stdpaths.h>
+
 
 // ----------------------------------------------------------------------------- : Debugging
 
@@ -26,6 +29,13 @@ SCRIPT_FUNCTION(get_mse_version) {
   SCRIPT_RETURN(app_version.toString());
 }
 
+SCRIPT_FUNCTION(get_mse_path) {
+  wxFileName app_path(wxStandardPaths::Get().GetExecutablePath());
+  String app_folder = app_path.GetPath();
+  app_folder.Replace("\\", "/");
+  SCRIPT_RETURN(app_folder);
+}
+
 SCRIPT_FUNCTION(trace) {
   SCRIPT_PARAM_C(String, input);
   #if defined(_DEBUG) && 0
@@ -770,6 +780,7 @@ SCRIPT_FUNCTION(rule) {
 void init_script_basic_functions(Context& ctx) {
   // debugging
   ctx.setVariable(_("get_mse_version"),      script_get_mse_version);
+  ctx.setVariable(_("get_mse_path"),         script_get_mse_path);
   ctx.setVariable(_("trace"),                script_trace);
   ctx.setVariable(_("warning"),              script_warning);
   ctx.setVariable(_("error"),                script_error);

tools/website/drupal/mse-drupal-modules/highlight.inc

@@ -104,6 +104,7 @@ $built_in_functions = array(
 	'write_set_file'	=>'',
 	// other
 	'get_mse_version'			=>'',
+	'get_mse_path'			=>'',
 	'trace'			=>'',
 	'assert'		=>'',
 	'exists_in_package'		=>'',