[REF] *: BS4, adapt forms

The 'form-horizontal' class have been removed; the '.form-group'
elements must now use the 'row' class for an horizontal layout.

The 'control-label' class was renamed to 'col-form-label'.

The 'help-block' class was renamed to 'form-text'.

The 'has-error' and 'has-success' classes have been removed and
replaced by a new system using the :valid and :invalid pseudo-classes,
when a parent has the 'was-validated' class. While this system is great,
it is not straightforward to use it in Odoo. Fortunately, BS4 provides
the 'is-valid' and 'is-invalid' classes as fallback. This commit
replaces the 'has-error' and 'has-success' classes by 'o_has_error' and
'o_has_success' classes (for JS compatibility) and use the 'is-*'
fallback classes. (The 'has-warning' class has no equivalent but was
unused in Odoo anyway).