Add support for specific builds of MSIE 9 on Win 7 SP1

These IE9 versions are vulnerable to MS14-012 (see #3120). If we don't add them, then os_detect might recognize the target as IE 8, and fail.

Before you test, make sure you have these IE patches (for 32-bit Win 7 SP1):
- [ ] IE9-Windows6.1-KB2909921-x86
- [ ] IE9-Windows6.1-KB2898785-x86
- [ ] IE9-Windows6.1-KB2888505-x86
- [ ] IE9-Windows6.1-KB2879017-x86
- [ ] IE9-Windows6.1-KB2870699-x86
- [ ] IE9-Windows6.1-KB2862772-x86

You'll have to install them individually in order to test:

- [x] Copy everything from os.js
- [x] And paste it in your IE's developer's tool
- [x] When you use ```os_detect.getVersion()```, it should show you that your IE is IE9 on Win 7 SP1.