use OS symbol in deploy

extra/tools/deploy/backend/backend.factor

@@ -107,6 +107,4 @@ DEFER: ?make-staging-image
     make-boot-image
     deploy-command-line run-factor ;
 
-SYMBOL: deploy-implementation
-
-HOOK: deploy* deploy-implementation ( vocab -- )
+HOOK: deploy* os ( vocab -- )

extra/tools/deploy/macosx/macosx.factor

@@ -50,17 +50,13 @@ IN: tools.deploy.macosx
 : bundle-name ( -- string )
     deploy-name get ".app" append ;
 
-TUPLE: macosx-deploy-implementation ;
-
-T{ macosx-deploy-implementation } deploy-implementation set-global
-
 : show-in-finder ( path -- )
     NSWorkspace
     -> sharedWorkspace
     over <NSString> rot parent-directory <NSString>
     -> selectFile:inFileViewerRootedAtPath: drop ;
 
-M: macosx-deploy-implementation deploy* ( vocab -- )
+M: macosx deploy* ( vocab -- )
     ".app deploy tool" assert.app
     "resource:" [
         dup deploy-config [

extra/tools/deploy/windows/windows.factor

@@ -25,11 +25,7 @@ IN: tools.deploy.windows
 : image-name ( vocab bundle-name -- str )
     prepend-path ".image" append ;
 
-TUPLE: windows-deploy-implementation ;
-
-T{ windows-deploy-implementation } deploy-implementation set-global
-
-M: windows-deploy-implementation deploy*
+M: winnt deploy*
     "." resource-path [
         dup deploy-config [
             [ deploy-name get create-exe-dir ] keep