feat(github): push force contributor branch.

.github/cpr.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 #
 # git config --global alias.cpr '!sh .github/cpr.sh'
 

.github/pfpr.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+#
+# git config --global alias.pfpr '!sh .github/pfpr.sh'
+
+set -e # stop on error
+
+usage="$(basename "$0") pr -- Push force a Pull Request branch"
+
+if [ "$#" -ne 1 ]; then
+    echo "Illegal number of parameters"
+    echo "$usage" >&2
+    exit 1
+fi
+
+command -v jq >/dev/null 2>&1 || { echo "I require jq but it's not installed.  Aborting." >&2; exit 1; }
+
+set -x # echo on
+
+initial=$(git rev-parse --abbrev-ref HEAD)
+pr=$1
+remote=$(curl -s https://api.github.com/repos/containous/traefik/pulls/$pr | jq -r .head.repo.owner.login)
+branch=$(curl -s https://api.github.com/repos/containous/traefik/pulls/$pr | jq -r .head.ref)
+
+git push --force-with-lease $remote $pr--$branch:$branch

.github/rmpr.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 #
 # git config --global alias.rmpr '!sh .github/rmpr.sh'
 

.github/rpr.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 #
 # git config --global alias.rpr '!sh .github/rpr.sh'
 
@@ -33,4 +33,4 @@ trap clean EXIT
 .github/cpr.sh $pr
 
 git rebase $base
-git push --force-with-lease $remote "$pr--$branch"
+git push --force-with-lease $remote $pr--$branch:$branch