AUTOTOOLS: More robust detection of inotify.
    
    We checked only header file "sys/inotify" for detection whether inotify
    works. Some platforms do not have built in inotify, but contain library,
    which provides inotify-compatible interface.
    
    This patch adds more robust detection of inotify in configuration time and
    appends linker flags to Makefile if inotify is provided by library.