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/pglab.pro

@@ -69,7 +69,11 @@ SOURCES += main.cpp\
     IndexModel.cpp \
     CrudTab.cpp \
     CrudModel.cpp \
-    PgLabItemDelegate.cpp
+    PgLabItemDelegate.cpp \
+    Module.cpp \
+    PglPage.cpp \
+    EditorGutter.cpp \
+    CodeEditor.cpp
 
 HEADERS  += \
     QueryResultModel.h \
@@ -110,7 +114,11 @@ HEADERS  += \
     IndexModel.h \
     CrudTab.h \
     CrudModel.h \
-    PgLabItemDelegate.h
+    PgLabItemDelegate.h \
+    Module.h \
+    PglPage.h \
+    EditorGutter.h \
+    CodeEditor.h
 
 FORMS    += mainwindow.ui \
 	ConnectionManagerWindow.ui \