UPD: Improve installer script (#1852)

install/windows/doublecmd.iss

@@ -1,16 +1,43 @@
 ; Script generated by the Inno Setup Script Wizard.
 ; SEE THE DOCUMENTATION FOR DETAILS ON CREATING INNO SETUP SCRIPT FILES!
+; Need Inno Setup 5 with pre-processor
+
+#define MyAppName           "Double Commander"
+#define                     MajorVersion    
+#define                     MinorVersion    
+#define                     RevisionVersion    
+#define                     BuildVersion    
+#define TempVersion         ParseVersion('doublecmd\doublecmd.exe', MajorVersion, MinorVersion, RevisionVersion, BuildVersion)
+#define DisplayVersion      str(MajorVersion) + "." + str(MinorVersion) + "." + str(RevisionVersion)
+#define MyAppAuthor         "Alexander Koblov"
+#define MyAppSupportURL     "https://doublecmd.sourceforge.io"
+#define StartCopyrightYear  "2006"
+#define CurrentYear         GetDateTimeString('yyyy','','')
 
 [Setup]
-AppName=Double Commander
-AppVerName=Double Commander Beta {#DisplayVersion}
+AppName={#MyAppName}
 AppVersion={#DisplayVersion}
-AppPublisher=Alexander Koblov
+AppVerName={#MyAppName} Beta {#DisplayVersion}
+
+VersionInfoProductName={#MyAppName}
+VersionInfoDescription={#MyAppName} Beta installer
+VersionInfoVersion={#DisplayVersion}
+
+UninstallDisplayName={#MyAppName} Beta
+UninstallDisplayIcon={app}\doublecmd.exe
+AppPublisher={#MyAppAuthor}
+
+AppCopyright={#StartCopyrightYear}-{#CurrentYear} {#MyAppAuthor}
 AppPublisherURL=https://doublecmd.sourceforge.io
 AppSupportURL=https://doublecmd.sourceforge.io
 AppUpdatesURL=https://doublecmd.sourceforge.io
-DefaultDirName={pf}\Double Commander
-DefaultGroupName=Double Commander
+
+ShowLanguageDialog=yes
+UsePreviousLanguage=no
+LanguageDetectionMethod=uilanguage
+
+DefaultDirName={pf}\{#MyAppName}
+DefaultGroupName={#MyAppName}
 AllowNoIcons=yes
 LicenseFile=doublecmd\doc\COPYING.txt
 OutputDir=release