Use PDO for MySQL queries (#8935)

Gut dbFacile
mres() now does nothing... could have some vulnerable queries, but most are ok

TODO
- [x] IRC client broke
- [x] Install broke

DO NOT DELETE THIS TEXT

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doc/Installation/Installation-CentOS-7-Apache.md

@@ -39,13 +39,10 @@ exit
 
     vi /etc/my.cnf
 
-> NOTE: Whilst we are working on ensuring LibreNMS is compatible with MySQL strict mode, for now, please disable this after mysql is installed.
-
 Within the `[mysqld]` section please add:
 
 ```bash
 innodb_file_per_table=1
-sql-mode=""
 lower_case_table_names=0
 ```
     systemctl enable mariadb

doc/Installation/Installation-CentOS-7-Nginx.md

@@ -39,13 +39,10 @@ exit
 
     vi /etc/my.cnf
 
-> NOTE: Whilst we are working on ensuring LibreNMS is compatible with MySQL strict mode, for now, please disable this after mysql is installed.
-
 Within the `[mysqld]` section please add:
 
 ```bash
 innodb_file_per_table=1
-sql-mode=""
 lower_case_table_names=0
 ```
     systemctl enable mariadb

doc/Installation/Installation-Ubuntu-1604-Apache.md

@@ -36,13 +36,10 @@ exit
 
     vi /etc/mysql/mariadb.conf.d/50-server.cnf
 
-> NOTE: Whilst we are working on ensuring LibreNMS is compatible with MySQL strict mode, for now, please disable this after mysql is installed.
-
 Within the `[mysqld]` section please add:
 
 ```bash
 innodb_file_per_table=1
-sql-mode=""
 lower_case_table_names=0
 ```
     systemctl restart mysql

doc/Installation/Installation-Ubuntu-1604-Nginx.md

@@ -35,13 +35,10 @@ exit
 
     vim /etc/mysql/mariadb.conf.d/50-server.cnf
 
-> NOTE: Whilst we are working on ensuring LibreNMS is compatible with MySQL strict mode, for now, please disable this after mysql is installed.
-
 Within the `[mysqld]` section please add:
 
 ```bash
 innodb_file_per_table=1
-sql-mode=""
 lower_case_table_names=0
 ```
     systemctl restart mysql