added install-dependences target to xbsv/Makefile

Change-Id: Iee59250ef8a0ecb1a0165459f56ec93b472a2333
added doc/Makefile

Change-Id: I265a1ef4a35152e866ee46bd9ba924422f5ee166
added sequence diagrams for requests and indications

Change-Id: I9cd74bbbe05b7d5e1056fa5510a516a7b7cefc9a
added a snapshot of the documentation

Change-Id: I859ded3c68b7f9dda6e6f8bc73eb8d47687ac725