added spec to verify default CTOR argument serialization is broken

[Aaronontheweb]

Ran into this issue in the wild; added a spec to verify.

[Aaronontheweb]

Error for Mono not showing up on checkmark due to #39, but it's here in the logs:

[21:29:10]	[docker] 
[21:29:10]	[docker] Test run for /checkout/Hyperion.Tests/bin/Release/netcoreapp1.0/Hyperion.Tests.dll(.NETCoreApp,Version=v1.0)
[21:29:11]	[docker] Microsoft (R) Test Execution Command Line Tool Version 15.0.0.0
[21:29:11]	[docker] Copyright (c) Microsoft Corporation.  All rights reserved.
[21:29:11]	[docker] 
[21:29:11]	[docker] Starting test execution, please wait...
[21:29:13]	[docker] [xUnit.net 00:00:01.0619402]   Discovering: Hyperion.Tests
[21:29:13]	[docker] [xUnit.net 00:00:01.3994812]   Discovered:  Hyperion.Tests
[21:29:14]	[docker] [xUnit.net 00:00:01.5054871]   Starting:    Hyperion.Tests
[21:29:14]	[docker] [xUnit.net 00:00:02.0633171]     Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(val1: True, val2: False) [FAIL]
[21:29:14]	[docker] [xUnit.net 00:00:02.0670384]       Assert.Equal() Failure
[21:29:14]	[docker] [xUnit.net 00:00:02.0671854]       Expected: False
[21:29:14]	[docker] [xUnit.net 00:00:02.0672427]       Actual:   True
[21:29:14]	[docker] [xUnit.net 00:00:02.0690800]       Stack Trace:
[21:29:14]	[docker] [xUnit.net 00:00:02.0782522]         /checkout/Hyperion.Tests/CustomObjectTests.cs(87,0): at Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(Boolean val1, Boolean val2)
[21:29:14]	[docker] [xUnit.net 00:00:02.0818967]     Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(val1: False, val2: True) [FAIL]
[21:29:14]	[docker] [xUnit.net 00:00:02.0820607]       Assert.Equal() Failure
[21:29:14]	[docker] [xUnit.net 00:00:02.0821049]       Expected: True
[21:29:14]	[docker] [xUnit.net 00:00:02.0825918]       Actual:   False
[21:29:14]	[docker] [xUnit.net 00:00:02.0826474]       Stack Trace:
[21:29:14]	[docker] [xUnit.net 00:00:02.0830364]         /checkout/Hyperion.Tests/CustomObjectTests.cs(87,0): at Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(Boolean val1, Boolean val2)
[21:29:14]	[docker] Failed   Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(val1: True, val2: False)
[21:29:14]	[docker] Error Message:
[21:29:14]	[docker]  Assert.Equal() Failure
[21:29:14]	[docker] Expected: False
[21:29:14]	[docker] Actual:   True
[21:29:14]	[docker] Stack Trace:
[21:29:14]	[docker]    at Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(Boolean val1, Boolean val2) in /checkout/Hyperion.Tests/CustomObjectTests.cs:line 87
[21:29:14]	[docker] Failed   Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(val1: False, val2: True)
[21:29:14]	[docker] Error Message:
[21:29:14]	[docker]  Assert.Equal() Failure
[21:29:14]	[docker] Expected: True
[21:29:14]	[docker] Actual:   False
[21:29:14]	[docker] Stack Trace:
[21:29:14]	[docker]    at Hyperion.Tests.CustomObjectTests.CanSerializeDefaultCtorArguments(Boolean val1, Boolean val2) in /checkout/Hyperion.Tests/CustomObjectTests.cs:line 87
[21:29:15]	[docker] [xUnit.net 00:00:03.0937879]     Hyperion.Tests.CollectionTests.CanSerializeMultiDimentionalArray [SKIP]
[21:29:15]	[docker] [xUnit.net 00:00:03.0939669]       add support for multi dimentional arrays
[21:29:15]	[docker] Skipped  Hyperion.Tests.CollectionTests.CanSerializeMultiDimentionalArray
[21:29:15]	[docker] [xUnit.net 00:00:03.4139414]   Finished:    Hyperion.Tests
[21:29:16]	[docker] 
[21:29:16]	[docker] Total tests: 119. Passed: 116. Failed: 2. Skipped: 1.
[21:29:16]	[docker] Test Run Failed.
[21:29:16]	[docker] Test execution time: 5.1388 Seconds

[Aaronontheweb]

Passes when both optional arguments are the same. Fails when they're different.