[FaceRest] Extract setting up HandlerArg from launchHandlerInTryBlock()
[FaceRest] Add FaceRest* arg to setupHandlerArg().

Because all members of HandlerArg should be set by setupHandlerArg().
[FaceRest] Remove setupHandlerArg(), use constructor of HandlerArg instead
[FaceRest] Revert efe05ef3.

Sorry, now I noticed that it's too ugly commit...
I'll retry to refine HandlerArg related code.
[FaceRest] Rename HandlerArg to RestMessage.

I'll add all informations of a HTTP message (SoupMessage, query,
SoupClientContext and so on) to this object.
Fix indent
[FaceRest] Store all arguments of setupRestMessage() to RestMessage
[FaceRest] Reduce arguments of RestHandler and related functions
[FaceRest] Don't ignore errors in setupRestMessage()
[FaceRest] Move parseFormatType() from FaceRest to RestMessage
[FaceRest] Move setupRestMessage() from FaceRest to RestMessage.

And rename to parse().
[FaceRest::RestMessage] Initialize members at constructor
[FaceRest] Move getJsonpCallbackName() from FaceRest to RestMessage
[FaceRest::RestMessage] Fix scope of some member functions
[FaceRest] Remove needless arguments from getParamWithErrorReply()
[FaceRest] Add queueMessage().

I'll add a queue mechanism using this function to realize
asynchronous server response.
Currently it just only replace launchHandlerInTryBlock().
[FaceRest::RestMessage] Add a destructor
[FaceRest] Rename RestMessage to RestJob
[FaceRest] Move pauseMessage() and unpauseMessage() to RestJob.

And renamed to pause() and unpause().
[FaceRest] Use meaningful variable names.

arg ->
job

handlerArg ->
restJon