Support data annotations for POCO mapping

[VitaliyMF]

DbDataAdapter Select/Insert/Update methods: handle System.ComponentModel.DataAnnotations.Schema.ColumnAttribute (NotMappedAttribute, DatabaseGenerated)

I think DbDataAdapter.Select(Query, IDictionary<string,string> fldMap) should be removed: custom mapping will be covered by DbDataAdapter for typed POCO in #13 .

Lets add RecordSet.FromList(IList list) method that will automatically infer RecordSet schema from poco. It should handle KeyAttribute, ColumnAttribute, NotMappedAttribute, DatabaseGeneratedAttribute.

[VitaliyMF]

Progress:

• refactored code that performs POCO mapping (DataMapper class).
• increased mapping performance (getters / setters are cached)
• removed overloads that accept IDicitonary<string,string> map for field (data annotations should be used instead)

Still TODO:

• Change DbDataAdapter Insert / Update signatures (incompatible API changes, but for alpha this is ok). They should use TableAttribute for poco object, if specified.
• RecordSet.FromList(IList list)

[VitaliyMF]

Done