better detection/extraction of existing sequences in H2

When EOF needs to generate new primary keys it uses sequences that follow a certain naming schema. If that sequence has not yet been created by EOF it will first check if there is already a sequence it can use before creating its own.

Instead of extracting the name of an existing sequences from the SQL expression stored in the information schema get it directly from the SEQUENCE_NAME field or alternatively extract it from the column with the default value definition.