Create (or find) a Hibernate dialect override to support unicode in SQL Server

[amcclain]

SQL server needs to use the nvarchar() type to support unicode content. On a related note, nvarchar(max) is the current unicode-ready replacement for text.

However the default GORM Hibernate mappings, even when using the latest org.hibernate.dialect.SQLServer2016Dialect still use the non-unicode compatible varchar and text types.

You can work around this on a per-field basis, i.e. with this mapping for a Comment class where we want the body field to support arbitrarily long strings of unicode text:

static mapping = {
        table name: 'comment', schema: 'dbo'
        body type: 'text', sqlType: 'nvarchar(max)'
        cache true
    }

But it would be great if we could include a Hibernate dialect within Hoist that a dev could specify to get unicode-by-default out of the box for string fields.