temporarily disable webapp on windows; re-enable webdav on windows

The gcc response file should make it build with webdav (fingers crossed).

webapp is waiting on a haskell platform upgrade on the autobuilder.
Current one has a too old version of network for hxt to install.

git-annex.cabal

@@ -124,7 +124,7 @@ Executable git-annex
     Build-Depends: hS3
     CPP-Options: -DWITH_S3
 
-  if flag(WebDAV) && (! os(windows))
+  if flag(WebDAV)
     Build-Depends: DAV (>= 0.3), http-conduit, xml-conduit, http-types
     CPP-Options: -DWITH_WEBDAV
 
@@ -163,7 +163,7 @@ Executable git-annex
   if flag(AndroidSplice)
     CPP-Options: -DANDROID_SPLICES
 
-  if flag(Webapp)
+  if flag(Webapp) (! os(windows))
     Build-Depends:
      yesod, yesod-default, yesod-static, yesod-form, yesod-core,
      case-insensitive, http-types, transformers, wai, wai-logger, warp,

standalone/windows/build.sh

@@ -6,10 +6,12 @@
 set -x
 set -e
 
+# Path to the Haskell Platform.
 HP="/c/Program Files (x86)/Haskell Platform/2012.4.0.0"
 
 PATH="$HP/bin:$HP/lib/extralibs/bin:/c/Program Files (x86)/NSIS:$PATH"
 
+# This tells git-annex where to upgrade itself from.
 UPGRADE_LOCATION=http://downloads.kitenet.net/git-annex/windows/current/git-annex-installer.exe
 
 # Run a command with the cygwin environment available.