[syscalls] Add ZX_POL_NEW_PROCESS

Previously, we lacked a policy bit for controlling process creation.
We'll use this policy bit in the future to force clients through
fuchsia.process.Launcher.

Also, hide ZX_POL_MAX from userspace so we can add more policy bits in
the future.

TEST=spawn_launcher_test

Change-Id: Idcba7c7db595774bd10b227da41e4c7249bb83ea

[syscalls] Remove legacy EVENTPAIR names

All the clients have been updated.

Change-Id: Ia96cc64aa82b14b4b3b774ba1a414c35b08a8e1e

[zircon] Normal spelling of EVENTPAIR

Previously, we had EPAIR, EVPAIR, and EVENT_PAIR. Now we just use
EVENTPAIR, to match the "eventpair" noun in the syscalls.

Change-Id: Id5b3b33aca02921980022e3d69acae40aaab9eae

[kernel][policy_manager] fix issue of querying policy for new timer object

In PolicyManager::QueryBasicPolicy(), function should return
the action for new_timer object instead of the action for
new_fifo object when query condition is ZX_POL_NEW_TIMER.

Change-Id: Ic7d1a9b669868e529e6c1ddcf6f3a3d03b0b8b0a

[zx] Magenta -> Zircon

The Great Renaming is here!

Change-Id: I3229bdeb2a3d0e40fb4db6fec8ca7d971fbffb94

[kernel][object] job policy update for timers

To line up with all the other objects that don't require
a parent handle the policy can now deny new timers.

Change-Id: Iff69f2c6f97322a4d30661b43eef955a7d7db7c8

[zircon][mxtl->fbl] Rename mxtl to fbl

Change-Id: Ie21b6498e1bfb0a7fa0315e40b9e5c3ee78646be

[lib/magenta] Rename kernel/lib/magenta to kernel/object

TODO: Rename magenta.{cpp,h} and other instances of "magenta" in this
module.

For MG-1091 "Rename kernel/lib/magenta"

Change-Id: I2abc316f543798e00d3a4d1c2c83195da26e6836