release process: split release.sh into two

This allows the add_cosigner workflow to be done before the website links to new binaries.
(so Emzy or other builders can try to reproduce builds and add signatures before new binaries are fully live)

contrib/trigger_deploy.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+# Triggers deploy.sh to maybe update the website or move binaries.
+# uploadserver needs to be defined in /etc/hosts
+
+SSHUSER=$1
+TRIGGERVERSION=$2
+if [ -z $SSHUSER ] || [ -z TRIGGERVERSION ]; then
+    echo "usage: $0 SSHUSER TRIGGERVERSION"
+    echo "e.g. $0 thomasv 3.0.0"
+    echo "e.g. $0 thomasv website"
+    exit 1
+fi
+set -ex
+cd "$(dirname "$0")"
+
+if [ "$TRIGGERVERSION" == "website" ]; then
+    rm -f trigger_website
+    touch trigger_website
+    echo "uploading file: trigger_website..."
+    sftp -oBatchMode=no -b - "$SSHUSER@uploadserver" << !
+       cd electrum-downloads-airlock
+       mput trigger_website
+       bye
+!
+else
+    rm -f trigger_binaries
+    printf "$TRIGGERVERSION" > trigger_binaries
+    echo "uploading file: trigger_binaries..."
+    sftp -oBatchMode=no -b - "$SSHUSER@uploadserver" << !
+       cd electrum-downloads-airlock
+       mput trigger_binaries
+       bye
+!
+fi
+