Support for INSERT, UPDATE and DELETE in multiple tables

[ngsankha]

Now INSERT, UPDATE and DELETE requests into multiple tables can be done from a single query. This reduces network latency in calls to the database server.

Now the Query object will look like:

UpdateQuery := {
    verb: "update",
    table: [table_name1, table_name2, ...]
    data: [{ column_name: Value, ... }, ...] | SelectQuery,
    filters: [{ column_name: Condition, ... }, ...], ?
    limit: count ?
}