Address recent SCST comments

The paches in this patch series address the following issues:
- Make sure that all SCST sysfs attributes have only one value per file.
- Remove the '[key]' marker from sysfs files since it is nonstandard.
- Replace the symbolic constant SCST_SYSFS_BLOCK_SIZE by PAGE_SIZE.
- Improved the robustness of the sysfs parsing code.
- Fixed the errors in the online documentation of /sys/devices/scst/mgmt.
- Correct the version number of the SCST core.
- Update the documentation in Documentation/ABI/stable according to the above changes.
- Made the SCST sysfs documentation more clear. All comments formulated by Greg and Konrad about the documentation in Documentation/ABI/stable should have been addressed.

Notes:
- In case anyone starts wondering why set commands were introduced instead of making sysfs files writeable: the reason behind this is to avoid lock inversion.
- While examining how SCST has been configured via the sysfs interface is straightforward, configuring SCST via sysfs can be tedious. There exists a user space tool that allows to save a configuration to disk and to restore a configuration, even without restarting SCST. The source code of that tool can be obtained as follows:

svn co https://scst.svn.sourceforge.net/svnroot/scst/branches/sysfs-tree-changes/scstadmin

An example of a configuration file generated by the scstadmin tool:

# Automatically generated by SCST Configurator v2.0.0.

HANDLER vdisk_fileio {
	DEVICE disk01 {
		filename /dev/vdisk1
		nv_cache 1
	}
	DEVICE disk02 {
		filename /dev/vdisk2
		nv_cache 1
	}
	DEVICE disk03 {
		filename /dev/vdisk3
		nv_cache 1
	}
	DEVICE disk04 {
		filename /dev/vdisk4
		nv_cache 1
	}
}

HANDLER vdisk_nullio {
DEVICE disk05
DEVICE disk06
DEVICE disk07
}

TARGET_DRIVER ib_srpt {
TARGET ib_srpt_target_0 {
rel_tgt_id 1
enabled 1

LUN 0 disk01
LUN 1 disk02
LUN 2 disk03
LUN 3 disk04
LUN 4 disk05
LUN 5 disk06

GROUP initiator1 {
INITIATOR 0x00000000000000000002c9030005f34b INITIATOR 0x00000000000000000002c9030005f34c LUN 0 disk01
LUN 1 disk02
LUN 2 disk03
LUN 3 disk04
LUN 4 disk05
LUN 5 disk06
LUN 6 disk07
}
}

TARGET ib_srpt_target_1 {
rel_tgt_id 2
enabled 1

LUN 0 disk01
LUN 1 disk02
LUN 2 disk03
LUN 3 disk04
LUN 4 disk05
LUN 5 disk06
}
}