Update NSIS installer to modern UI

deploy/qgroundcontrol_installer.nsi

+!include "MUI2.nsh"
+
 Name "QGroundcontrol"
+Var StartMenuFolder
 
 InstallDir $PROGRAMFILES\qgroundcontrol
 
-Page license 
-Page directory
-Page components
-Page instfiles
-UninstPage uninstConfirm
-UninstPage instfiles
+!define MUI_HEADERIMAGE
+!define MUI_HEADERIMAGE_BITMAP "installheader.bmp";
+
+!insertmacro MUI_PAGE_LICENSE "license.txt"
+!insertmacro MUI_PAGE_STARTMENU Application $StartMenuFolder
+!insertmacro MUI_PAGE_DIRECTORY
+!insertmacro MUI_PAGE_INSTFILES
+
+!insertmacro MUI_UNPAGE_CONFIRM
+!insertmacro MUI_UNPAGE_INSTFILES
 
-LicenseData license.txt
+!insertmacro MUI_LANGUAGE "English"
 
 Section
   SetOutPath $INSTDIR
@@ -50,10 +57,10 @@ done:
 SectionEnd 
 
 Section "Uninstall"
+  !insertmacro MUI_STARTMENU_GETFOLDER Application $StartMenuFolder
   SetShellVarContext all
-  Delete $INSTDIR\QGroundControl_uninstall.exe
   RMDir /r /REBOOTOK $INSTDIR
-  RMDir /r /REBOOTOK "$SMPROGRAMS\QGroundControl\"
+  RMDir /r /REBOOTOK "$SMPROGRAMS\$StartMenuFolder\"
   SetShellVarContext current
   RMDir /r /REBOOTOK "$APPDATA\QGROUNDCONTROL.ORG\"
   DeleteRegKey HKLM "Software\Microsoft\Windows\CurrentVersion\Uninstall\QGroundControl"
@@ -61,8 +68,8 @@ SectionEnd
 
 Section "create Start Menu Shortcuts"
   SetShellVarContext all
-  CreateDirectory "$SMPROGRAMS\QGroundControl"
-  CreateShortCut "$SMPROGRAMS\QGroundControl\QGroundControl.lnk" "$INSTDIR\qgroundcontrol.exe" "" "$INSTDIR\qgroundcontrol.exe" 0
+  CreateDirectory "$SMPROGRAMS\$StartMenuFolder"
+  CreateShortCut "$SMPROGRAMS\$StartMenuFolder\QGroundControl.lnk" "$INSTDIR\qgroundcontrol.exe" "" "$INSTDIR\qgroundcontrol.exe" 0
 SectionEnd
 
 Function .onInit