Fix a race condition in status.test

Mhash del function was used incorrectly, resulting in memory access past
the buffer end.

Add a separate error code for the case when a tuple is too large
(larger than slab_alloc_maximal).
The test suite already covered the case.

Conflicts:
	src/lib/small

Improve style for Terminal session blocks

docs: fix multiple issues

Clean up unused and broken references
Clean up trailing whitespaces
Improve formatting in Digest reference
Add remaining hotlinks to Configuration book
Fix mistakes

Restyle Bash sessions in Connectors

Remove unused files

Conflicts:
	src/box/box.cc
	src/box/cluster.cc
	src/lib/small

server_id should be checked in on_replace trigger instead of
box_on_cluster_join().

With recent osx toolchains gcc is an alias for clang.