Update Windows installer readme for including QT GUI and other installer improvements.

win_installer/readme.txt

@@ -1,11 +1,12 @@
 Windows installer for the cppcheck
 ----------------------------------
 
-Simple Windows installer installing executable, license file and readme.txt to
-program files/cppcheck folder.
+Windows installer for both command line cppcheck and for QT-based GUI. All
+needed runtimes and libraries are installed.
 
-Shortcuts are created to start cmd.exe in installation folder. So when the user
-selects start menu/desktop icon he gets command prompt in cppcheck folder.
+Command line cppccheck shortcuts are created to start cmd.exe in installation
+folder. So when the user selects start menu/desktop icon he gets command prompt
+in cppcheck folder.
 
 Get the InnoSetup from:
 http://www.innosetup.com/
@@ -13,10 +14,14 @@ Be sure to download the 'QuickStart Pack' as it installs some nice tools
 like ISTool and preprocessor support.
 
 Files the installer needs:
-/Release/cppcheck.exe
 /COPYING
 /readme.txt
 /AUTHORS
+/gui/release/gui.exe
+/Release/cppcheck.exe
+/win_installer/icon.bmp
+/win_installer/LargeLogo.bmp
+/win_installer/
 
 NOTE: Remember to convert COPYING and AUTHORS to Windows EOL format! Otherwise
 Windows Notepad (default viewer) can't show then properly.
@@ -30,6 +35,14 @@ and modify RuntimesFolder -macro in begin of cppcheck.iss to point to the
 folder where files are. You can find runtime files from VS installation or from
 net.
 
+QT Libraries:
+Visual Studio is used to build the GUI executable. And QT must be build with VS
+also. When building QT make sure you build release targets!
+
+Copy following files to same RuntimesFolder than VS runtime files:
+- QtCore4.dll
+- QtGui4.dll
+
 Creating the installer executable:
 #1 Open the ISTool and load cppcheck.iss
 #2 Update the release version number: