Cover basics of CREATE INDEX.
Add support for index names.
Maintain index names in Lua.

Fix memory leaks this test has revealed.

 * sys/prctl.h can be found only on Linux, but cmake recognizes Debian/kFreeBSD
 as Linux.
 * extern "C" for TIMEOUT_INFINITY (it is used in plugins)

https://blueprints.launchpad.net/tarantool/+spec/auto-init-storage

Add basic tests for space DDL, fix bugs the test coverage
has revealed.

Conflicts:
	test/box/net.box.result

Fix race condition in session.test.

Modify 'space' object contents when altering it, rather
than create a new Lua table.
In Lua, when saving a copy of a table in a local variable
a shallow copy is saved, in other words, table variables
initialized from each other share state.

Make use of this feature in the following scenario:

space = box.schema.create_space()
space:create_index() -- modifies box.space[id] which 'space' is a
shared ptr to
space.index[0] - great, space.index[0] has the added index.