[WIP] Added the config file for appveyor.com continuous integration

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Related tickets | 
| License       | GNU GPL v3

https://ci.appveyor.com/project/alquerci/cyg-apt

Full patched build with #34, #35, #36, #37: https://ci.appveyor.com/project/alquerci/cyg-apt/build/1.0.81