Preliminary filesystem module skeleton implementation
Fixed compilation problems
Management interface preliminary implementation (sysfs)
SysFS directories for snapfs mount points

More complete support for sysfs directories, corresponding to snapfs
mount points: splitted sysfs entries construction for mount points;
still the same data storage for mount_point_path file.
SnapFS mount points list and kobjects for every mount point

Work-in-progress
Separate KObjects for filesystem mount points

FS module is maintaining list of mount points and appropriate KObjects
with attributes in SysFS.
Mount point's attributes are not separated yet, though.
Error handling and memory management improvements

Don't forget to free allocated memory.
Increment mount points counter only when setup_snapfs_mount_point_mgmt
succeeded.
Fix mount point attribute show/store functions logging
Mount points attributes "separation"

Dummy function to get snapfs_mount_point structure by kobject.
mnt_point_show_path for mnt_point_path_attr.
State, Next state (next state/stare change request) attributes
Store mount point kobject in snapfs_mnt_point as a value, not pointer

Use container_of (in snapfs_mnt_point_for_kobj function) to determine snapfs_mnt_point structure for kobject passed to attributes show/store functions.
INode operations lookup method skeleton

Skeleteon method finally traverses super blocks list in the way we need.

Tried to revert .gitignore.
Remove kobject's forward declaration
Delete next state attribute
INode lookup redirection, directory open/readir dumb wrappers
Update nd.inode and argument dentry.d_sb too
Comment on nameidata argument changes in snapfs_inode_lookup