stat64 has been changed to return jiffies granuality as nsec in previously
unused fields. This allows make to make better decisions on when
to recompile a file. Follows losely the Solaris API.

CURRENT_TIME has been redefined to return struct timespec.  The users
who don't use it in a inode/attr context have been changed to use a new
get_seconds() function.  CURRENT_TIME is implemented by an out-of-line
function.

There is a small performance penalty in this patch.  The previous
filemap code had an optimization to flush atime only once a second.
This is currently gone, which will increase flushes a bit.  I believe
the correct solution if it should be a problem is to have per super
block fields that give an arbitary atime flush granuality - so that you
can set it to be only flushed once a hour if you prefer that.  I will
work on that later in separate patches if the need should arise.

struct inode and the attr struct has been changed to store struct
timespec instead of time_t for [cma]time.  Not all file systems support
this granuality, but some like XFS,NFSv3,CIFS,JFS do.  The others will
currently truncate the nsec part on flushing to disk.  There was some
discussion on this rounding on l-k previously.  I went for simple
truncation because there is not much evidence IMHO that the more
complicated roundings have any advantages.  In practice application will
be rather unlikely to notice the rounding anyways - they can only see a
difference when an inode is flush from memory and reloaded in less than
a second, which is rather unlikely.