Make moving a directory safer

When moving a directory, the call for creating the new obejct should
be done before removing the old one. This way, if there is a problem,
at the old path object is kept.
Set the right ctime when creating a directory

The ctime is now considered the real creation time of the directory
instead of being set to the modification time.
Set the ctime correctly when statting a dir
Move radosfs_debug out of the namespace

This is so the call can be used in methods that do not belong to that
namespace.
Set the mtime when creating or modifying a dir
Set the correct mtime when statting a directory
Add setter/getter for the directory's TM time

A change in a file or directory will set the TM (transversal
modification) time of the parent directories if they have this
property enabled.
Add a method for updating the dirs' TM time
Add updateDirTimes method to RadosFsPriv

This is a convenient method for setting the 'mtime' and 'tmtime'
of a directory.
Update dirs' times when calling modifying methods
Add an overloaded stat method that outputs tmtime
test: Add unit tests to check the directories' times
Rename updateDirTimeAsync to updateTimeAsync

Also renamed the updateDirTimeAsyncCB analogously.
Update the files' 'mtime' when writing/truncating
Set the right ctime when creating a file
Set the right time when statting a file
test: Add unit tests for the files' times
Don't update FsInfo in FsFile::updatePermissions

It is not needed.
Stat objects according to their path's appearance

By default it was always trying to stat objects as directories and
only statting them as files after thist first approach failed.

This patch changes that and stats the objects according to what their
path looks like -- if it has an ending /, try to stat as a directory
first, otherwise try to stat as a file. This will improve performance
for cases where the paths are correctly representing their objects,
which always happen when e.g. listing and statting a directory's
contents.
Get the file size when getting its last stripe

Instead of making two calls -- one to stat the file stripe and
another to get its size -- this patch calls those together in the
same operation.