ui: Custom style for dock widget title bars

* avoid style loading in every view on application start
* improved contrast of reference label
* moved Reset Window Layout action up in View menu

bin/app/data/gui/main/main.css

@@ -0,0 +1,31 @@
+QToolTip {
+	background-color: #E0E0E0;
+	color: black;
+	font-size: <setting:font_size>px;
+}
+
+QMainWindow::separator {
+	background: <color:window/separator>;
+	width: 1px;
+}
+
+QDockWidget {
+	color: <color:window/dock/text>;
+	font-size: 10pt;
+	titlebar-close-icon: url(<setting:gui_path>main/images/close_<color:window/dock/icon_type>.png);
+	titlebar-normal-icon: url(<setting:gui_path>main/images/float_<color:window/dock/icon_type>.png);
+}
+
+QDockWidget::title {
+	border-bottom: 1px solid <color:window/dock/line>;
+	background: <color:window/dock/background>;
+	text-align: center;
+	padding-top: 1px;
+}
+
+QDockWidget::close-button, QDockWidget::float-button {
+	background: transparent;
+	border: none;
+	icon-size: 12px;
+	margin-top: 2px;
+}

bin/app/data/gui/main/scrollbar.css

@@ -0,0 +1,62 @@
+QScrollBar:vertical, QScrollBar:horizontal {
+	background: <color:window/scrollbar/background>;
+	border: none;
+	margin: 0px;
+}
+
+QScrollBar:vertical {
+	width: 15px;
+	border-left: 1px solid <color:window/scrollbar/line>;
+}
+
+QScrollBar:horizontal {
+	height: 15px;
+	border-top: 1px solid <color:window/scrollbar/line>;
+}
+
+QScrollBar::handle:vertical, QScrollBar::handle:horizontal {
+	background: <color:window/scrollbar/handle>;
+	border: none;
+	border-radius: 4px;
+}
+
+QScrollBar::handle:vertical {
+	width: 8px;
+	min-height: 16px;
+	margin: 4px 3px;
+}
+
+QScrollBar::handle:horizontal {
+	height: 8px;
+	min-width: 16px;
+	margin: 3px 4px;
+}
+
+QScrollBar::add-line:vertical, QScrollBar::add-line:horizontal {
+	background: transparent;
+	border: none;
+	height: 0px;
+	width: 0px;
+	subcontrol-position: bottom;
+	subcontrol-origin: margin;
+}
+
+QScrollBar::sub-line:vertical, QScrollBar::sub-line:horizontal {
+	background: transparent;
+	border: none;
+	height: 0px;
+	width: 0px;
+	subcontrol-position: top;
+	subcontrol-origin: margin;
+}
+
+QScrollBar::add-page:horizontal, QScrollBar::sub-page:horizontal, QScrollBar::add-page:vertical, QScrollBar::sub-page:vertical {
+	background: none;
+}
+
+QAbstractScrollArea::corner {
+    background: transparent;
+    border: none;
+    border-left: 1px solid <color:window/scrollbar/line>;
+    border-top: 1px solid <color:window/scrollbar/line>;
+}