- rename class to ColumnSchemaBuilder as this is more appropriate
- changed internal organisation to match how the rest of schema related classes work
- the ColumnSchemaBuilder is now created the same way as QueryBuilder is
- removed static call magic and method annotations, now real methods are called as they are
- the whole code works on objects in a db context now instead of setting database connection in global state
- trait is now used by Migration by default but can be used in other contexts as well
Migration usage is now as follows:
```php
$this->createTable('example_table', [
'id' => $this->primaryKey(),
'name' => $this->string(64)->notNull(),
'type' => $this->integer()->notNull()->defaultValue(10),
'description' => $this->text(),
'rule_name' => $this->string(64),
'data' => $this->text(),
'created_at' => $this->datetime()->notNull(),
'updated_at' => $this->datetime(),
]);
```
in this cases it does not make sense to remove duplicates as the result is not on record level anymore.
This could be the case after GROUP BY has been applied.
fixes#8772