relax SVN archive

The spin viewer menus and pipe switching elements are now disabled when the execution lock is on.

The menus IDs now are set with class variables using wx.NewId().

Many of the 'File' menu entries are now disabled when the execution lock is on.

The main menu IDs are now all class variables called self.MENU_* and are given by wx.NewId().

The pipe editor window is starting inactive if the execution lock is on.

The pipe editor window is now acquiring the pipe lock prior to updating its contents.

This removes a lot of race conditions, as the pipes can often change which the update occurs.

Most of the data pipe functions are now using the data pipe locking object status.pipe_lock.

The functions which acquire the lock object and which modify the pipe state include:
copy()
create()
delete()
switch()

The functions which acquire the lock object to prevent changes while they execute include:
display()
pipe_loop()

Created a lock object for the relax data pipes.

This will be used to prevent races in the GUI when data pipe info is accessed, but when a thread is
changing the data pipes at the same time.

The pipe editor window methods are now deactivated when the execution lock is on.

This prevents the user from doing something silly!

The execution lock is properly locked or released before notifying the observers.

This will remove some race conditions where the locked() method is called before the acquire() or
release() methods terminate.

The original zoom level is available in the relax controller log control pop up menu.