Update schema_fill.lua: space.n is renamed to space.id
Fix a failing Mac OS X build.

vclock.h is now a C header, and in clang C you can't
declare a structure in a for loop.
Fix spelling in an error message.
Simplify server bootstrap.

Instead of manually adding a surrogage server id for snapshot,
add it to the cluster clock when saving a snapshot.
Use vclock object in log_decode_setlsn().

Extract and document vclock merge logic.
Remove vclock_set() from vclock API

There are 3 cases of vclock update:
- add a new server (vclock_add_server())
- get the next lsn for a local server (vclock_inc())
- update a vclock copy from some remote master (vclock_follow()).
Merge a few redundant structures in replication relay code.

Simplify replication relay code. Rename a global variable
to a name that doesn't match a type name (simplifies debugging).
Remove a piece of code which is no longer used.
Word police:

node -> server
lsnmap -> vector clock
setlsn -> vclock
Improve wording of an error messages (Peter's comment).
Refactor xlog search logic to use vclockset tree
Final fixes for SCL building
Merge branch 'stable'

Conflicts:
	extra/rpm.spec.in
	extra/rpm/tarantool.rpm.spec.in
	test/CMakeLists.txt
Merge branch 'master' of https://github.com/tarantool/tarantool