Current state of duchain/parser

[Kris Wong]

> A few comments in the order that I see them.
>
> In duchainlock.h
> 1. No semi-colons in empty constructors. Just the brackets. Compilers
have 
> started to warn about this, and it's better to just avoid it all
together.

Okay.

> 2. Is there a particular reason why you used Qt::HANDLE? Everything in
the 
> documentation says this is pretty non portable.

It is what QReadWriteLock uses internally, and also what
QThread::currentThreadID returns.  I tried to match QReadWriteLock where
possible while still providing the functionality we needed.

> 3. Unline the ReadLocker and WriteLocker methods if you can. I don't
know
> what the compiler does with those in debug mode, but i'd prefer to be
able
> to debug it if needed.

It does not inline them when optmizations are turned off (technically it
might not inline them even if they are turned on).  I can certainly
remove the inline keywords, though.

Kris Wong