Bug in StringConverter

Backslashes weren't escaped.
New connection Pgsql84Connection & some debugs
fromDb debug

Timestamp::fromDb('') returns now null value
Correction for : PgSQL OFFSET, Hstore, and Table->count
fixed SQL cast, added findOne($criteria, $order, $forupdate)
Ajout de Mysqli
Debug de JsonConverter et de MySQL/TimestampConverter
translate($type) added ton ConverterInterface

A converter have now a translate method wich return the right SQL Type.
Delete common converters, due to the translate method
create / drop added to the connection & the table class
Add hasChanged() method to know if the Entity will be inserted or updated in the DB
Debug typo in count()
Update README.md
Ajout de l'option forUpdate dans findOne
Debug findOneBy($property, $value, $forUpdate)
Fix getTableClassName to return the good TableClassname
Fix: getTableClassName

Models could not start with \Models\...
Add: escape($value, $type) method
Add: escape methode and escapeString, escapeBinary are abstract
Fix: Add throw FieldFormatException in the convertToDb method
Fix: settype doesnt return the new value, it update the variable