Add IntelliSense on Common Methods and Objects

[Turnerj]

This is primarily for types that the user has a high chance of directly interacting with. When a concrete type has an interface, the comments should be on the interface. Visual Studio can pull the IntelliSense summary up through to the concrete type automatically. Any IntelliSense comments on concrete types already can be removed once corresponding ones are added to the interfaces.

The following types, along with their properties and methods, should have IntelliSense added:

• IMongoDbConnection
• IMongoDbContext / IMongoDbTenantContext
• IMongoDbSet / IMongoDbBucketSet / IMongoDbTenantSet
• MongoDbUtility
• IHaveTenantId
• BucketSetOptionsAttribute
• DbSetOptionsAttribute
• ExtraElementsAttribute
• IgnoreExtraElementsAttribute
• IndexAttribute (along with IndexType and IndexSortOrder enums)
• RuntimeTypeDiscoveryAttribute
• EntityEntryContainer
• EntityEntry
• LinqExtensions
• QueryableAsyncExtensions

The reason for not doing the other infrastructure classes is that the core of MongoFramework is still unstable and could easily have the IntelliSense comments needing to be rewritten multiple times. The ones listed above would benefit the most people using the system.