Allow Process Hacker to view the context of a thread

[AzAgarampur]

Feature Request It would be nice to view the context of a thread.

Additional information We can already inspect a thread to view its stack, so I was thinking it'd be neat if we could see the thread's context from NtGetThreadContext either in another window or alongside the callstack. This would be very helpful for me when I'm doing some debugging and working on some reverse-engineering projects. GPR's should be always shown, and we can make XMM/MMX registers optional in the list.