Add ClassDB binding for File.get_modified_time

Closes #7613

(cherry picked from commit 5ec0610c606f529b21ffc13596ae5a57ead368cb)

core/bind/core_bind.cpp

@@ -1822,6 +1822,11 @@ Variant _File::get_var() const {
 	return v;
 }
 
+uint64_t _File::get_modified_time(const String &p_file) const {
+
+	return FileAccess::get_modified_time(p_file);
+}
+
 void _File::_bind_methods() {
 
 
@@ -1870,6 +1875,7 @@ void _File::_bind_methods() {
 	ObjectTypeDB::bind_method(_MD("get_pascal_string"),&_File::get_pascal_string);
 
 	ObjectTypeDB::bind_method(_MD("file_exists","path"),&_File::file_exists);
+	ObjectTypeDB::bind_method(_MD("get_modified_time", "file"),&_File::get_modified_time);
 
 	BIND_CONSTANT( READ );
 	BIND_CONSTANT( WRITE );

core/bind/core_bind.h

@@ -459,6 +459,8 @@ public:
 
 	bool file_exists(const String& p_name) const; ///< return true if a file exists
 
+	uint64_t get_modified_time(const String& p_file) const;
+
 	_File();
 	virtual ~_File();