Merge #225: sync-upstream: Use --autostash to handle uncommitted changes

13c438c sync-upstream: Use --autostash to handle uncommitted changes (Tim Ruffing)

Pull request description:

  This makes it possible to use sync-upstream with uncommitted changes. (This is in particular helpful when working on the script itself.)

  Without this commit, git pull will fail due to the uncommitted changes.

ACKs for top commit:
  apoelstra:
    utACK 13c438c

Tree-SHA512: c3a2fce68382bf4e769c64bbdc5666a8f4d9cf6f387e7d8af408e9c3e07b4a875205b7cdae9f647b7127128c13ee58effc0045ac5faf5fba2851b38af40439e8

contrib/sync-upstream.sh

@@ -97,7 +97,7 @@ echo "$BODY"
 echo "-----------------------------------"
 # Create branch from PR commit and create PR
 git checkout master
-git pull
+git pull --autostash
 git checkout -b temp-merge-"$PRNUM"
 
 # Escape single quote