Restructure bind tests

diff --git a/t/47bind_attribute.t b/t/bind/attribute.t
similarity index 100%
rename from t/47bind_attribute.t
rename to t/bind/attribute.t

diff --git a/t/bindtype_columns.t b/t/bind/bindtype_columns.t
similarity index 100%
rename from t/bindtype_columns.t
rename to t/bind/bindtype_columns.t

diff --git a/t/order/with_bind.t b/t/bind/order_by.t
similarity index 100%
rename from t/order/with_bind.t
rename to t/bind/order_by.t