[server][testHatoholArmPluginInterface] Add 'override' keyword to a override method.
[mlpl][SmartBuffer] Add a const qulifier so that it can be called from a const object.
[mlpl][SmartBuffer] Can specify any start index of getPointer().
[server][HatoholArmPluginInterface] Add a mechanism to call a command callback function.
[server] Define __STDC_LIMIT_MACROS to avoid the build error on Ubuntu 12.04 (g++4.6).
[server] Aggregate C++ compiler options to make the management easy.
[server][testDBClientUser] Fix a duplicated definition.
[mlpl][SimpleSemaphore] Add a new method: timedWait().
[server][HatoholArmPluginInterface] Use two queues for bidirectional communication.
[server][HatoholArmPluginGate] Add override keyword to an overridden method.
[server][HatoholArmPluginGate] Launch plugin processes after the connection with an AMQP broker is established.

This is to avoid the problem in which a plugin process tried to
connect with an AMQP broker before the queue is created.
[server][testHatoholArmPluginGate] Replace GMainLoop with SimpleSemaphore.

There are two reasons.

(1) The previous code stalls if quit() is called before run().
(2) New code eliminates the timer handler. As a result, the number
of code has been reduced.
[server][testHatoholArmPluginInterface] Use SimpleSemaphore instead of GMainLoop.

The reasons are the same as 00e6117a.
[server][testHatoholArmPluginInterface] Clean up.
[server][testHatoholArmPluginInterface] Use 'const' for a const variable.
[server] Add a new stub class HatoholArmPluginBase.

This class will be a base class of concreate plugins.
[server] Rename a variable to be suitable for the current code.

runMainLoop ->
waitMainSem

Recently the synchronization mechanism has been changed from
the GMainLoop-based to the SimpleSemaphore-based. So the
variable was changed to follow it.
[server][HatoholArmPluginInterface] Show detailed status.
[server][HatoholArmPluginInterface] Change the log level.
[server][HatoholArmPluginInterface] Insert an article.