-m is not accepted in hub pull-request

## Bad Examples

```
∴ hub pull-request -m "Fix spec suite typo; All tests now pass" -b sevos:master -h pboling:fix-specs
invalid argument: Fix spec suite typo; All tests now pass
```

```
∴ hub pull-request -m "All tests now pass" -b sevos:master -h pboling:fix-specs
invalid argument: All tests now pass
```

## Good example

```
∴ hub pull-request "Fix spec suite typo; All tests now pass" -b sevos:master -h pboling:fix-specs
https://github.com/sevos/zeus-parallel_tests/pull/28
```