MDEV-33407 Parser support for vector indexes

The syntax is

  create table t1 (... vector index (v) ...);

limitation:
* v is a binary string and NOT NULL
* only one vector index per table
* temporary tables are not supported

MDEV-33404 Engine-independent indexes: subtable method

added support for so-called "high level indexes", they are not visible
to the storage engine, implemented on the sql level. For every such
an index in a table, say, t1, the server implicitly creates a second
table named, like, t1#i#05 (where "05" is the index number in t1).
This table has a fixed structure, no frm, not accessible directly,
doesn't go into the table cache, needs no MDLs.

MDEV-33406 basic optimizer support for k-NN searches

for a query like SELECT ... ORDER BY func() optimizer will use
item_func->part_of_sortkey() to decide what keys can be used
to resolve ORDER BY.

This partially reverts 43623f04

Engines have to set ::position() after ::write_row(), otherwise
the server won't be able to refer to the row just inserted.
This is important for high-level indexes.

heap part isn't reverted, so heap doesn't support high-level indexes.
to fix this, it'll need info->lastpos in addition to info->current_ptr

needed to get partitioning and information about
secondary objects

the information about index algorithm was stored in two
places inconsistently split between both.

BTREE index could have key->algorithm == HA_KEY_ALG_BTREE, if the user
explicitly specified USING BTREE or HA_KEY_ALG_UNDEF, if not.

RTREE index had key->algorithm == HA_KEY_ALG_RTREE
and always had key->flags & HA_SPATIAL

FULLTEXT index had  key->algorithm == HA_KEY_ALG_FULLTEXT
and always had key->flags & HA_FULLTEXT

HASH index had key->algorithm == HA_KEY_ALG_HASH or HA_KEY_ALG_UNDEF

long unique index always had key->algorithm == HA_KEY_ALG_LONG_HASH

In this commit:

All indexes except BTREE and HASH always have key->algorithm
set, HA_SPATIAL and HA_FULLTEXT flags are not used anymore (except
for storage to keep frms backward compatible).

Bounded_queue<> pretended to be a typesafe C++ wrapper
on top of pure C queues.h.

But it wasn't, it was tightly bounded to filesort and only useful there.

* implement Queue<> - a typesafe C++ wrapper on top of QUEUE
* move Bounded_queue to filesort.cc, remove pointless "generalizations"
  change it to use Queue.
* remove bounded_queue.h
* change subselect_rowid_merge_engine to use Queue, not QUEUE

as it can never be null (only "" or "disabled")

ASAN builds pass so it's ok

let ALL PRIVILEGES to always mean ALL PRIVILEGES over all
upgrades, no matter what new privileges were added in later versions.

allow RPM upgrades from a different minor version,
if the major version is the same.

This was needed as mtr --embedded connect.alter failed as online is
ignored for embedder server.
This fixes a wrong commit 30c965f8

This was caused by the patch for
MDEV-32567 Remove thr_alarm from server codebase

During the build process this is wrapped into plugin_auth.h.

MariaDB debian control files are slightly in disorder
run wrap-and-sort tool against them shows some minor
changes.

Fix Debian .install files to alphabetically ordered from
mostly ordered state.

After MDEV-31400, plugins are allowed to ask for retries when failing
initialisation. However, such failures also cause plugin system
variables to be deleted (plugin_variables_deinit()) before retrying
and are not re-added during retry.

We fix this by checking that if the plugin has requested a retry the
variables are not deleted. Because plugin_deinitialize() also calls
plugin_variables_deinit(), if the retry fails, the variables will
still be deleted.

Alternatives considered:

- remove the plugin_variables_deinit() from plugin_initialize() error
handling altogether. We decide to take a more conservative approach
here.

- re-add the system variables during retry. It is more complicated
than simply iterating over plugin->system_vars and call
my_hash_insert(). For example we will need to assign values to
the test_load field and extract more code from test_plugin_options(),
if that is possible.

followup for abcd23ad

it was able to enable --ssl-verify-server-cert if explicily requested,
now it can also disable it, if explicitly requested.

In case of failure, the something like the following is now printed:

Slave position:  file: binary.000004  position: 3647
Master position: file: binary.000004  position: 3647