Refactor, removing optional parameters.
Refactor. Method overload instead of optional parameters
by @damiangreen. Added Time limit head information to base Response class.
Unused usings
Merge branch 'master' of https://github.com/InstaSharp/InstaSharp

Conflicts:
	src/InstaSharp/Endpoints/Locations.cs
	src/InstaSharp/Endpoints/Tags.cs
	src/InstaSharp/Extensions/HttpClientExtensions.cs
	src/InstaSharp/Models/Realtime.cs
	src/InstaSharp/Models/Responses/Response.cs
	src/InstaSharp/Models/Tag.cs