Since Go 1.7, context is a standard package. Since Go 1.9, everything
that is provided by "x/net/context" is a couple of type aliases to
types in "context".
Many vendored packages still use x/net/context, so vendor entry remains
for now.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This makes separating middlewares from the core api easier.
As an example, the authorization middleware is moved to
it's own package.
Initialize all static middlewares when the server is created, reducing
allocations every time a route is wrapper with the middlewares.
Signed-off-by: David Calavera <david.calavera@gmail.com>