This patch replaces region_*() functions with xregion_*() functions.

NO_DOC=refactoring
NO_TEST=refactoring
NO_CHANGELOG=refactoring

(cherry picked from commit 1ba84fe3)

In some cases unsafe extension decoding was done without bound and type
checks: add necessary checks.

Closes tarantool/security#73

NO_DOC=bugfix

(cherry picked from commit 1de6a071)

Part of #6773

NO_DOC=Will be added later.
NO_CHANGELOG=Will be added later.

This patch fixes an assertion or segmentation fault when getting the
value of MP_EXT via netbox.

Closes #6766

NO_DOC=Bugfix

Part of #6773

NO_DOC=Doc-request will be added in another commit.
NO_CHANGELOG=Changelog will be added in another commit.

After this patch, MAP values can be used as bind variables. However, due
to the current syntax for binding in Lua, the only possible way is to
use MAP values as the named bind variable.

Part of #4763

After this patch, ARRAY values can be used as bind variables. However,
due to the current syntax for binding in Lua, the only possible way is
to use ARRAY values as the named bind variable.

Part of #4762

Some of the code is no longer used after changes in the SQL built-in
functions. This patch removes part of the unused code.

Needed for #4145

After this patch, DECIMAL values can be bound like any other supported
by SQL values.

Closes #4717

After this patch, uuid values can be bound like any other supported by
SQL values.

Part of #6164

Region is used for temporary allocations, usually bound to a
transaction, but not always. Keyword - temporary. It is usually
much faster to allocate something on the region than on the heap,
and much much faster to free the region, since it frees data in
whole slabs. Lots of objects at once.

Region is used both for byte arrays (MessagePack, strings, blobs),
and for objects like standard types, structs. Almost always for
allocations was used region_alloc() function, which returns a not
aligned address. It can be anything, even not multiple of 2.

That led to alignment violation for standard types and structs.
Usually it is harmless in terms of errors, but can be slower than
aligned access, and on some platforms may even crash. Also the
crash can be forced using clang undefined behaviour sanitizer,
which revealed all the not aligned accesses fixed in this patch.

Part of #4609

Let's follow unified naming rules for SQL high level API which
manipulates on statements objects. To be more precise, let's use
'sql_stmt_' prefix for interface functions operating on statement
handles.

This patch allows to operate on integer values in range [2^63, 2^64 - 1]
It means that:
 - One can use literals from 9223372036854775808 to 18446744073709551615
 - One can pass values from mentioned range to bindings
 - One can insert and select values from mentioned range

Support of built-in functions and operators has been introduced in
previous patches.

Closes #3810
Part of #4015

Removing this error code is part of getting rid of the SQL error
system.

Removing this error/status code is part of getting rid of the SQL
error system.

The bindings mechanism was not updated in scope of BOOLEAN static
type patch. Fixed.

This patch provides straightforward refactoring replacing enum sql_type
with enum mp_type. Note that we use msgpack format instead of field_type
since it is more suitable when dealing with NULLs.

Exported sql_bind structure, sql_bind_decode, sql_bind_column
and sql_bind routines in separate module bind.h. We need SQL
bindings in further pathes with check constraints. Also, bind
encapsulated in execute.c prevent us from implementation of a Lua
part of forthcoming box.execute().

Needed for #3691, #3505