Added an instruction in 'How to deploy' field in README.md

Signed-off-by: Babu Shanmugam <anbu@enovance.com>
Modifed the String variables in db.py to be of fixed length to support databases which doesn't have VARCHAR support

Signed-off-by: Babu Shanmugam <anbu@enovance.com>
Following changes are made
1. Increased the String length for distro, version and os_desc columns in osds_info table
2. Corrected version information extraction in client/ceph-brag
3. Removed the version_id json entry when version list returned for UUID
4. Updated the README to reflect point 3

Signed-off-by: Babu Shanmugam <anbu@enovance.com>
In database delete Session.flush() has to be called appropriately, to avoid foreign key conflicts in delete() request to the database

Signed-off-by: Babu Shanmugam <anbu@enovance.com>