Support "Named Value Dictionaries"

[mfenniak]

The long overdue capability to support free-form data objects inside rethinkdb-net without relying on the rethinkdb-net-newtonsoft add-on library. This will also add many dictionary operations to the key capabilities.

• Support converting Dictionary<string,object> round-trip to RethinkDB.
• Automatically detect the best object type to deserialize for a given RethinkDB value.
  • numbers -> double or int
  • objects:
    • special case: byte array
    • special case: DateTimeOffset
    • named value collection
  • string
  • bool
  • arrays....
    • string arrays -- all types are string or null gets a string[]
    • number arrays -- all types are int gets in int[], all types are int or null gets an int?[], all types are int or double gets a double[], all types are int or double or null gets a double?[]
    • all types are the same and or null, and the type is a reference type, gets a TReferenceType[]
    • all types are the same and or null, and the type is a value type, gets a TValueType?[]
    • throw an error; unable to find a homogenous array type. In the future, maybe we'd support a heterogeneous type like object[]
• Dictionary operations:
  • .ContainsKey(...)
  • .ContainsValue(...) No ReQL operation for this (and, why would you want to anyway?)
  • Count property No ReQL operation to find the number of keys in an object.
  • Keys property
  • Values property
  • Item accessors; eg. dictionary[key], for getting.
  • Item accessors; eg. dictionary[key], for setting. Doesn't return a Dictionary type, so can't make it work in a LINQ expression. Created an alternative instead (next point).
  • Extension method to set a dictionary value in an Update query; dict.SetValue(key, value).SetValue(key2, value2)
  • .Add(...) method Returns void, can't use; however, SetValue extension method above does same functional capability.
  • .Remove(...) method No exact match for this in ReQL, but, did implement .Without() to exclude a key from a dictionary.
• Do useful things with the values of a dictionary; since they're of type object, this might require supporting casts in the expression converter. eg. .Filter(o => (int)o.FreeformProperties["awesome level"] > 10)
• Update release notes.
• How hard would it be to support dictionaries other than <string,object> now that most of the above work is done? --> easy; this has been implemented. Dictionary values can now be strongly typed or weakly typed by using System.Object.