Cleanup exposed interface

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
Remove original interface and implementations

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
Rename http2 transport to spdy

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
Update new interface naming to naming of original interface

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)