Support insertId and other optional params in Tabledata.insertAll

[nashyeung]

In my use case, I use BigQuery::Client::Tables.insert with large arrays frequently. Sometimes they succeed partially, i.e. half rows of a batch are added, the other half fail.

Instead of checking the results and only resending the failed rows (so the good rows are not sent twice), I want to add insertId to each row, then let Google do the de-duplication for us.

This is the main purpose of this PR.

It's quite hard to add insertId support to the existing insert() method without changing its interface, so I create a new insert_all().