reworked resultsets

[bendlas]

First two commits are essential. Caveat: Please make sure, that the behavior with :fetch-size is desired in with-results

With the middle two commits I reworked result-seq in the following ways:

• duplicate cols with different values are not auto aggregated into vectors anymore

  • that code path didn't work in the first place due to bugs in non-unique-map;

  had it worked, it would have led to horrendous non-determinism on spurious equal values

• instead, duplicate columns with different values throw
  • which approximates the behavior of resultset-seq modulo false negatives and throw-time (lazyness)

• lazyness kicks in before the first record is created, hence before the first ResultSet is pulled

  that behavior is different to resultset-seq, where the first ResultSet is pulled immediately; should make no difference

• cleanup

The last commit changes result-seq to use transients

cheers