Support DynamicParameters and Output Parameters

[darthmolen]

Currently there is no support for Dynamic Parameters. Dapper uses a different code path for this object type over the anonymous object type. Additionally, it uses an outputCallback to fill in any parameters that are output types. Because there is no persistent mock for non-templated variables, each time Dapper tries to append a parameter to the query, it gets a new Parameters collection instead, causing an NRE. This needs to be solved for.

[andresmoschini]

Is there a workaround for this issue?