move derived tab bar from editor and doc viewer into separate file * file-editor.cc (file_editor_tab_bar::file_editor_tab_bar), (file_editor_tab_bar::create_context_menu), (file_editor_tab_bar::mousePressEvent): remove all functions related to the derived file_editor_tab_bar class; (file_editor_tab_widget::file_editor_tab_widget): use the new tab_bar; (file_editor::construct): add the close actions to the context menu provided by tab_bar * file-editor.h: derived tab bar removed * module.mk: new files tab_bar.cc and tab_bar.h * webinfo.cc (webinfo) use new tab_bar instead of special webinfo_tab_bar, connect tab bar signal for closing tab; (webinfo_tab_bar::webinfo_tab_bar), (webinfo_tab_bar::mousePressEvent): removed * webinfo.h: removed webinfo_tab_bar * tab-bar.cc: new tab bar for editor and doc viewer derived from QTabBar; (tab_bar): constructor, create context menu; (mousePressEvent): reimplemented mouse press event for detecting mouse actions for closing a tab, in case, emitting related signal * tab-bar.h: new tab bar for editor and doc viewer derived from QTabBar

--- a/libgui/src/module.mk	Fri Feb 02 14:16:30 2018 -0800
+++ b/libgui/src/module.mk	Sat Feb 03 09:51:34 2018 +0100
@@ -110,6 +110,7 @@
   %reldir%/moc-settings-dialog.cc \
   %reldir%/moc-terminal-dock-widget.cc \
   %reldir%/moc-color-picker.cc \
+  %reldir%/moc-tab-bar.cc \
   %reldir%/moc-resource-manager.cc \
   %reldir%/moc-shortcut-manager.cc \
   %reldir%/moc-welcome-wizard.cc \
@@ -167,6 +168,7 @@
   %reldir%/resource-manager.h \
   %reldir%/settings-dialog.h \
   %reldir%/shortcut-manager.h \
+  %reldir%/tab-bar.h \
   %reldir%/thread-manager.h \
   %reldir%/terminal-dock-widget.h \
   %reldir%/color-picker.h \
@@ -200,6 +202,7 @@
   %reldir%/resource-manager.cc \
   %reldir%/settings-dialog.cc \
   %reldir%/shortcut-manager.cc \
+  %reldir%/tab-bar.cc \
   %reldir%/thread-manager.cc \
   %reldir%/terminal-dock-widget.cc \
   %reldir%/color-picker.cc \