[gimp] Installer: better error message about unsupported OS

[Jernej Simončič <jernejs src gnome org>]

commit 5427d82d21f4a4e8d9064d2775ec0c9edc2f3791
Author: Jernej Simončič <jernej|s-cccp eternallybored org>
Date:   Thu May 10 17:18:34 2018 +0200

    Installer: better error message about unsupported OS

 build/windows/installer/gimp3264.iss      |    2 +-
 build/windows/installer/lang/setup.isl.in |    1 +
 2 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/build/windows/installer/gimp3264.iss b/build/windows/installer/gimp3264.iss
index f05508f..50d729f 100755
--- a/build/windows/installer/gimp3264.iss
+++ b/build/windows/installer/gimp3264.iss
@@ -145,7 +145,7 @@ InternalCompressLevel=ultra
 SolidCompression=yes
 LZMAUseSeparateProcess=yes
 LZMANumFastBytes=273
-LZMADictionarySize=524288
+LZMADictionarySize=1048576
 
 ;SignTool=Default
 SignedUninstaller=yes
diff --git a/build/windows/installer/lang/setup.isl.in b/build/windows/installer/lang/setup.isl.in
index 42684e1..bde195f 100644
--- a/build/windows/installer/lang/setup.isl.in
+++ b/build/windows/installer/lang/setup.isl.in
@@ -6,6 +6,7 @@
 _WizardInfoBefore=License Agreement
 _AboutSetupNote=Setup built by Jernej Simonèiè, jernej-gimp ena si
 _WinVersionTooLowError=This version of GIMP requires Windows 7, or a newer version of Windows.
+_WindowsVersionNotSupported=This version of GIMP requires Windows 7, or a newer version of Windows.
 
 [CustomMessages]
 ;shown before the wizard starts on development versions of GIMP