Fixes #102.

The NuGet packages for SqlitePCL.raw underwent name changes.
Updated the nuget package names, and had to manually add
SqlitePCL.raw-basic package first, as the SqlitePCL.ugly
package was picking up the (older) cached package instead.
Merge pull request #107 from couchbaselabs/xam-beta2-fix

Fixes #102.