ClickOS: Add new MiniOS driver [1/2]

Patch click to build on top of MiniOS.
ClickOS: Add new MiniOS driver [2/2]

Add the main application.
Packet: Increase default_headroom under CLICK_OS

Improve performance by reduce the number of memory reallocations.
sync: Implement SimpleSpinlock on MiniOS

This implementation of a spinlock is arguably but it works for our
purposes now.
timerset: Implement lock mechanism on MiniOS
routerthread: Add fence()

*Experimental, only available for ClickOS*
The fence() function blocks as long as run_task() is being executed
routerthread: Don't run_task() if master is paused

Only available for ClickOS
Add suspend/resume hooks

Add hooks to elements for router suspend and resume.

Each element should declare a suspend_phase (similar to the
configure_phase), used by the router to determine the order in which the
elements will be suspended. A router will call the suspend hook at least
once on every element, in suspend_phase order. Only when all elements
sharing the same suspend_phase return a successful suspend elements from
lower phase are suspended.

Elements are resume in inverse suspend_phase order.
MiniOS: Add FromDevice element
MiniOS: Add ToDevice element
clickos: Check read handler requests validity
minios: Remove unnecessary defines from conf hdr
minios: Compile with HAVE_PORTABLE_LLRPC

This is a workaround for compilation problems in some situations where
_IOC_DIRSHIFT is not defined. We should take a look at this later on.
minios: Provide placement new only when necessary
click: Fix indentation in config.h.in
minios/click: Remove unnecessary includes
minios: Include mini-os code as extern "C" [1/2]

MiniOS headers are not cpp safe. This commit patches click code.
minios: Include mini-os code as extern "C" [2/2]

This commit patches click.cc.
minios/driver: Initialize NotifierSignal

This was initially disable because of compilation issues that don't
exist anymore.
clickos: Set f_stop flag on router init error

This was preventing the guest from shutdown in case of a failed router
initialization.