Cleanup Loading and NavState code, there's currently additional calls to both which are slightly confusing (and don't provide any benefit).
So simplify by setting SetIsLoading(true) on LoadStart and SetIsLoading(false) on LoadEnd. Then only set NavState in ClientAdapter::OnLoadingStateChange
Add navigation type to IRequest.
Update ManagedCefBrowserAdapter.h

Check if _webBrowserInternal is null before checking if it is Initialized.
Update ManagedCefBrowserAdapter.h

Fix tab format to use spaces instead.
Merge pull request #561 from kropewnicki/master

Update ManagedCefBrowserAdapter.h to check for a null pointer in OnInitialized method
Merge branch 'feature/add-request-navigation-type' of https://github.com/Evgest/CefSharp into upstream-master
Move NavigationType into it's own class
Rename NavigationType to TransitionType (keeping inline with Cef API)
Change to using statement rather than namespace qualified declerations
Rename NavigationType property to TransitionType
Add xml comment to TransitionType
Change TransitionType to an unit enum
Add [Falgs] attribute as TransitionType can have multiple values
Import values from cef_transition_type_t (cef_types.h)
Rename some of the values (slightly friendlier names)
Add license disclaimer
Merge pull request #564 from amaitland/feature/transitionType

Add Transition Type to IRequest
Merge pull request #539 from amaitland/cleanup/loading-navstate

Cleanup Loading and NavState code
Add navigation type to IRequest.
Move NavigationType into it's own class
Rename NavigationType to TransitionType (keeping inline with Cef API)
Change to using statement rather than namespace qualified declerations
Rename NavigationType property to TransitionType