push and create pull request

push zsh

```
function push() {
  local result st a
  result=$(git push 2>&1 -u origin `git branch | grep \* | cut -d ' ' -f2`)
  st=$?

  if [ $st = 0 ]; then
    a=$(echo "$result" | grep 'Create a pull request for')
    if [ -n "$a" ]; then
      git brws --pr
    fi
  else
    echo 'git push failed.'
  fi

  echo $result
  return $st
}
```