Allow interaction when unmounting mounts

For details, see bug 587482. The new api:

 - Provide new _with_operation() variants of all unmount and eject methods

 - Add GMountOperation::show-processes signal
   - this can be used to show processes blocking an unmount operation

 - Deprecate all unmount and eject methods

 - Add g_drive_can_start_degraded() method
   - this is to avoid auto-starting degraded drives

 - Make g_drive_stop() resp. g_file_stop_mountable() take a GMountOperation
   - these ops were recently added and not yet public API so it's fine
     to change how they work

 - Provide a way to poll mountable files, e.g. g_file_poll_mountable()

 - Add some missing file attributes for mountable files
  - G_FILE_ATTRIBUTE_MOUNTABLE_UNIX_DEVICE_FILE
    - needed for the GDU Nautilus extensions to format a volume
  - G_FILE_ATTRIBUTE_MOUNTABLE_CAN_START_DEGRADED:
    - mimics g_drive_can_start_degraded()
  - G_FILE_ATTRIBUTE_MOUNTABLE_CAN_POLL:
    - mimics g_drive_can_poll_for_media()
  - G_FILE_ATTRIBUTE_MOUNTABLE_IS_MEDIA_CHECK_AUTOMATIC
    - mimics g_drive_is_media_check_automatic()

docs/reference/gio/Makefile.am

@@ -83,9 +83,11 @@ INCLUDES = \
 	-I$(top_srcdir)			\
 	-I$(top_srcdir)/glib		\
 	-I$(top_srcdir)/gobject		\
+	-I$(top_srcdir)/gio		\
 	-I$(top_builddir)		\
 	-I$(top_builddir)/glib		\
 	-I$(top_builddir)/gobject	\
+	-I$(top_builddir)/gio		\
 	$(GLIB_DEBUG_FLAGS)
 
 GTKDOC_LIBS = \

docs/reference/gio/gio-docs.xml

@@ -24,8 +24,8 @@
         <xi:include href="xml/gfileattribute.xml"/>
     	<xi:include href="xml/gfileinfo.xml"/>
 	<xi:include href="xml/gfileenumerator.xml"/>
-	<xi:include href="xml/gmountoperation.xml"/>
 	<xi:include href="xml/gioerror.xml"/>
+	<xi:include href="xml/gmountoperation.xml"/>
     </chapter>
     <chapter id="file_mon">
     	<title>File System Monitoring</title>
@@ -145,6 +145,9 @@
   <index>
     <title id="index-all">Index</title>
   </index>
+  <index role="deprecated">
+    <title>Index of deprecated symbols</title>
+  </index>
   <index role="2.18">
     <title>Index of new symbols in 2.18</title>
   </index>

docs/reference/gio/gio-sections.txt

@@ -149,12 +149,18 @@ g_file_mount_mountable
 g_file_mount_mountable_finish
 g_file_unmount_mountable
 g_file_unmount_mountable_finish
+g_file_unmount_mountable_with_operation
+g_file_unmount_mountable_with_operation_finish
 g_file_eject_mountable
 g_file_eject_mountable_finish
+g_file_eject_mountable_with_operation
+g_file_eject_mountable_with_operation_finish
 g_file_start_mountable
 g_file_start_mountable_finish
 g_file_stop_mountable
 g_file_stop_mountable_finish
+g_file_poll_mountable
+g_file_poll_mountable_finish
 g_file_mount_enclosing_volume
 g_file_mount_enclosing_volume_finish
 g_file_monitor_directory
@@ -249,8 +255,12 @@ G_FILE_ATTRIBUTE_MOUNTABLE_CAN_MOUNT
 G_FILE_ATTRIBUTE_MOUNTABLE_CAN_UNMOUNT
 G_FILE_ATTRIBUTE_MOUNTABLE_CAN_EJECT
 G_FILE_ATTRIBUTE_MOUNTABLE_UNIX_DEVICE
+G_FILE_ATTRIBUTE_MOUNTABLE_UNIX_DEVICE_FILE
 G_FILE_ATTRIBUTE_MOUNTABLE_HAL_UDI
+G_FILE_ATTRIBUTE_MOUNTABLE_CAN_POLL
+G_FILE_ATTRIBUTE_MOUNTABLE_IS_MEDIA_CHECK_AUTOMATIC
 G_FILE_ATTRIBUTE_MOUNTABLE_CAN_START
+G_FILE_ATTRIBUTE_MOUNTABLE_CAN_START_DEGRADED
 G_FILE_ATTRIBUTE_MOUNTABLE_CAN_STOP
 G_FILE_ATTRIBUTE_MOUNTABLE_START_STOP_TYPE
 G_FILE_ATTRIBUTE_TIME_MODIFIED
@@ -970,11 +980,15 @@ GMountMountFlags
 GMountUnmountFlags
 g_mount_unmount
 g_mount_unmount_finish
+g_mount_unmount_with_operation
+g_mount_unmount_with_operation_finish
 g_mount_remount
 g_mount_remount_finish
 g_mount_can_eject
 g_mount_eject
 g_mount_eject_finish
+g_mount_eject_with_operation
+g_mount_eject_with_operation_finish
 g_mount_guess_content_type
 g_mount_guess_content_type_finish
 g_mount_guess_content_type_sync
@@ -1008,6 +1022,8 @@ g_volume_mount_finish
 g_volume_can_eject
 g_volume_eject
 g_volume_eject_finish
+g_volume_eject_with_operation
+g_volume_eject_with_operation_finish
 G_VOLUME_IDENTIFIER_KIND_HAL_UDI
 G_VOLUME_IDENTIFIER_KIND_LABEL
 G_VOLUME_IDENTIFIER_KIND_NFS_MOUNT
@@ -1038,6 +1054,7 @@ g_drive_get_volumes
 g_drive_can_eject
 g_drive_get_start_stop_type
 g_drive_can_start
+g_drive_can_start_degraded
 g_drive_can_stop
 g_drive_can_poll_for_media
 g_drive_poll_for_media
@@ -1047,6 +1064,8 @@ g_drive_is_media_check_automatic
 g_drive_is_media_removable
 g_drive_eject
 g_drive_eject_finish
+g_drive_eject_with_operation
+g_drive_eject_with_operation_finish
 g_drive_start
 g_drive_start_finish
 g_drive_stop