Fixed ObservableReleasesClient.GetAssets

to use the correct url.
Fixing some unit tests that were not doing

any assertions.
Adding Received() where it was missing.
The majority of these instances were unawaited AssertEx.Throws
They are now all either awaited or replaced with Assert.Throw
Assert.Throw was used when possible and when not an option
AssertEx.Throw was awaited.
Merge branch 'bad_assets_url' into nonfunctioning_tests
Added missing methods on IRepositoriesClient

Added unit tests for newly added methods
Added models RepositoryTag, RepositoryLanguage and RepositoryUpdate
Added missing methods on IObservableRepo...

sitoriesClient
Added unit tests for new methods.
Added integration tests for new methods on...

RepositoriesClient
Merge branch 'master' of https://github.com/octokit/octokit.net into nonfunctioning_tests
Fixing AuthorizationsClientTests.

TheGetOrCreateApplicationAuthenticationMethod.WrapsTwoFactorFailureWi...
thTwoFactorException while I'm in here.
Added stats/contributors client & response objects

Not a fan of those suppress messages on weekly hash. Will see if we can
clean this up :soon:
Stubbed implementation of IStatisticsClient
Updated signature to include repo name and owner

Also return a list of contributors because.reasons (being that is what
the api returns)
renamed parameter
Implement client
Test stats client get contributors
:lipstick: renamed to GetContributors
Added Statistics Client
:lipstick:
ObservableStats Client
Observable Client tests
Added intergration tests for contributors api