Added simple thread group to the project
in order to run the asio callbacks.

The ThreadGroup class uses a simple list of threads because it is made
to create threads once and joine all threads once.

WIP: Making the whole core thread safe using mutexes.

All generators were sharing the same methods but with duplicate code.
Now the generators inherit from an abstract implementing the common code

We now use the main process ressources to process requests.
The main process is considered to be part of the processing threads.

On stopping signal, no longer clean the sessions before the handlers
are finished running.
This removes memory errors, leaks, bad_weak_ptr and bad file descriptors

Now stopping io_context to prevent any callback push in the queue
during a graceful exit.
Added it to monitoring thread too.

Getting back to accepting sessions one by one
because of strange behaviour.
Still WIP.

Applied the generator changes to the log filter.

Added a mutex to the log filter because of undefined behaviour
using filestreams in a threaded environment.

Added a mutex to access the cache in read/write because it is not
thread safe natively.

Updated fconnection generator to match prior updates
(06fd113)

Updated fhostlookup generator to match prior updates
(06fd113)

The host db of fhostlookup is thread safe for multiple reader with no
writer.

…ding

### CMAKE
- updated C++ version to 14 to 17

### Redis Manager
- works for heavy multithreading
- supports individual connections for each thread
- supports master/slave connections
- easy query, wide response types (int, string, array)
- automatic disconnection/reconnection timeouts (default 20 seconds)
- keep alive thread
- fallback to slave connection if master failed and slave exists
- stills connects to IP:port or unix sockets

### Redis Manager
- added first tests
  - simple master connect
  - slave -> master connect
  - slave -> master connect, master fail
  - slave -> master connect, master off
  - master connect, disconnect/reconnect after timeout

Correcting warnings due to worng initialization order of class members.

Updated fdga generator to match prior updates
(06fd113)

faup_hadler_t is unique for a given entry thus making it not thread safe.
Now passing options to thread because they will only be read safely.
Now faup_handler is created when we treat a new entry.

Updated fuseragent generator to match prior updates
(06fd113)

Now properly closing tensorflow session when all execution are finished.
(fdga & fuseragent)

Added the Workflow method to the Session class as it is
shared by all the filters.

Removed Workflow method from fdga.

Upadted Session to close on client connection interruption
only (without crashing).

Removed include of maxminddb from DGA Generator because useless.

FDGA threading hand-tested on Ubuntu 19.04.

Removed Workflow methods from filters to comply to
6cab130 :
  - fconnection
  - fhostlookup
  - flogs

Using lock_guars and unique_lock instead of raw mutex.

Reducing use of the _setMut mutex to the very minimum needed.

Removed the thread_id because it was set but never used.

Updated finspection generator to match prior updates
(06fd113)

- rename implementation of TCP states to avoid conflicts (GNU implementation not used as order of definitions is important)
- add conditional inclusion for assert()

This is a WIP because fanomaly now compiles but is not tested
thus not considered stable.

Tests and stability will come for  version 1.1.

… add_threading

This is a WIP because fsession now compiles but is not tested
thus not considered stable.

Tests and stability will come for  version 1.1.

Threads are useful on this filter in order to be able to process a lot of
entries simultaneously.

The workflow of the "cron" thread is not impacted.

… add_threading

Fixed by removing old class method from the hpp file.

As fend is going to be deleted in a close future
we remove it from default compilation.

As we no longer use freputation we remove it from default compilation.

We no longer provide support for those filters.

Co-Authored-By: frikilax <[email protected]>

Co-Authored-By: frikilax <[email protected]>

Co-Authored-By: frikilax <[email protected]>

Co-Authored-By: frikilax <[email protected]>

Co-Authored-By: frikilax <[email protected]>

Co-Authored-By: frikilax <[email protected]>