Added a gutter and currentline highlighting to the SQL editor.

Currently gutter only shows linenumbers. Code is mostly from http://doc.qt.io/qt-5/qtwidgets-widgets-codeeditor-example.html

There is a little bit included in this commit from a first try to make toobars adept to the current tab.

Code #2

pglab/Module.h

@@ -0,0 +1,15 @@
+#ifndef MODULE_H
+#define MODULE_H
+
+namespace Leon {
+
+class Module
+{
+public:
+	Module();
+
+};
+
+}
+
+#endif // MODULE_H