Improvements for debugging.

• Added Cbor_debug version flag that enables checks for putting data into sink. When enabled you will get a message that your sink size is smaller than data size like: Provided sink length is to small. Sink.$ 16380 < Data.$ 32768.
• Improved error message when the number of deserialized members doesn't match in form: The number of deserialized members of MyStruct is mismatched. Got 3, while expected 2 members.
• Made template numEncodableMembers public. Now you can check how many members will be actually encoded.