Merge pull request #479 from git-for-windows/drop-windows-7-windows-8-0-support

installer: drop support for Windows 7 and 8.0

Author: rimrul

installer/install.iss

@@ -95,6 +95,7 @@ WizardImageBackColor=clWhite
 WizardImageStretch=no
 WizardImageFile={#SourcePath}\git.bmp
 WizardSmallImageFile={#SourcePath}\gitsmall.bmp
+MinVersion=6.3
 
 [Types]
 ; Define a custom type to avoid getting the three default types.