Changed method for setting authentication on command
Resolve #53 Added commands and tests for predefined groups

This allows Procon security section to define two very common use-cases
for the security groups, one being an Administrator with complete access
to all functions and the other as an external streaming service to login
and setup a stream.
#54 Prevented users from removing their account
#54 Added dispatch group test on command executor

Checks if the command executor belongs to a group.
#54 Additional test on account removal prevention
#54 Prevented users from removing their group
Updated all nuget packages

Required alterations to repository package cache building and unit
tests. Requesting the latest version of a package seems to work now, so
the entire cache rebuild should be more efficient
Scrubbed null/default values from configs and transport

A lot of data was being transferred for no reason. Was a problem with
changes made to serialize interface->concrete that was ignoring original
serializer options to remove null values. 210 kB config is now about 30
kB and the savings should be similar for pushing events.
Moved plugin config test to a more implementation test

It was almost a double up of another test as-is, but this way it's
distinct from the other test being a full implementation of saving a
plugin config enable command
Split tests for GetAccount into their own file

Also cleaned up the tests with CommandBuilder
Split tests for SecurityRemoveAccount command
Split the remaining commands in TestAccount into their own files

Also simplified all of them with CommandBuilder and removed a bunch of
Assert's that didn't add to the test
Split security tests into their own namespaces

Finding the tests for a specific command was getting a little bit old.
Now at least the account commands are in their own namespace, so it's
much easier to work with.
Split the account player test into each command
Simplified permissions unit tests with CommandBuilder