sms_sender (smpp 3.4)

1. Use CentOS 7 (RHEL7-based) with kernel 3.10 or AlmaLinux 8 (RHEL8-based) with kernel 4.18.
2. Compiler GCC must be installed (exists at CentOS 7 Minimal install / AlmaLinux 8 Minimal install).
3. Use locale=en_US.UTF-8.
4. Put the file "sms_sender.zip" (or "sms_sender_alma8.zip") to /opt (or another dir).
5. "cd /opt" + "unzip sms_sender.zip".
6. "cd /opt/sms_sender" + "chmod +x sms_sender_1.exe".
7. For run "./ sms_sender_1.exe".
8. Fill the configuration file "/opt/sms_sender/sms_sender.cfg".
9. For stop (example for all services) "./sms_sender_1.exe stop".
10. For restart "./sms_sender_1.exe restart".
11. For reload configuration "./sms_sender_1.exe reload_cfg".
12. For use systemd "./sms_sender_1.exe use_systemd" and follow the instructions.

For create sms_sender_0dsm.exe just "cd /dir_with_sms_sender_1.exe" + "cp sms_sender_1.exe sms_sender_0dsm.exe".

For create sms_sender_0rx.exe just "cd /dir_with_sms_sender_1.exe" + "cp sms_sender_1.exe sms_sender_0rx.exe".

20211020 = Corrected config-history feature.

20211115 = Documentation updated (about feature "simple_chat").

20211117 = simple_chat - some changes for logging. After start config 'simple_chat.cfg' will be created automatically. Feature is not fully tested at this time.

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Bug1

Please, always fill configuration block [CONNECT_SPEED]