Change cmake minimum required version to 2.8.

Use copy_directory for Sophia and LuaJIT, this should
fix stupid errors when rebuilding after a pull.
Exclude src/trivia/config.h from source install.

Merge box.digest from stable

Conflicts:
	src/lua/init.cc
	test/box/lua.result

Conflicts:
	test/module/net_sql.mysql.result
	test/module/net_sql.mysql.test
	test/module/net_sql.pg.result
	test/module/net_sql.pg.test

Conflicts:
	src/box/CMakeLists.txt

* Remove a bogus message at the start of FindLibUUID.cmake.
* Move cluster_add_node to cluster.
* Extract UUID API into a (potentially) platform-independnent header
  tt_uuid.
* Add error codes for error messages used in UUID generation,
  triggers and consistency checks.
* Cleanup.

If ${MODULE_${type}} is absolute - do not prepend with ${CMAKE_INSTALL_PREFIX}

Add pagezero-size magic to link flags on Mac OS X,
as is required by LuaJIT.
The flag was dropped in my patch which changed the linking
scheme for the main executable.
On the same token, check for return value of luaL_newstate(),
and panic if it returns NULL, this should simplify
problem analysis in the future.

Conflicts:
	src/ffisyms.cc
	src/tarantool.cc

Conflicts:
	debian/control