Firebird dialect support

**Blocked by:**
https://github.com/devastool/entity2jooq/issues/27

**Description:**
1) Need to create `FirebirdTypeMapper` class, that extends from `DialectTypeMapper`, dialect name should be `Firebird`;
Example:
```java
public class FirebirdTypeMapper extends DialectTypeMapper {
public FirebirdTypeMapper() {
super("Firebird", Set.of(...))
}
}
```
2) Need to add new dialect to `RouteTypeMapper` constructor.
Example:
```java
public RouteTypeMapper() {
FirebirdTypeMapper firebirdMapper = new FirebirdTypeMapper();
dialects.put(firebirdMapper.getDialect(), firebirdMapper);
}
```