A whole bunch of N1QL regressions in recent Vulcan builds

I believe we have seen this problem before when Sitaram Vemulapalli made changes to go-couchbase (see MB-29034). Those changes have been reverted and the regressions have been recovered.

Sitaram's patch was re-introduced again in build 5.5.0-2546 and performance numbers got worse again.

See:
http://showfast.sc.couchbase.com/#/timeline/Linux/n1ql/Q1_Q3/MOI
http://showfast.sc.couchbase.com/#/timeline/Linux/n1ql/Q1_Q3/Plasma
http://showfast.sc.couchbase.com/#/timeline/Linux/n1ql/Q5_Q7/all
http://showfast.sc.couchbase.com/#/timeline/Linux/n1ql/array/all
http://showfast.sc.couchbase.com/#/timeline/Linux/n1ql/pagination/MOI
http://showfast.sc.couchbase.com/#/timeline/Linux/n1ql/soe/all

These test results are very consistent and I am very positive that we have a product issue.

Please let me know if you disagree with my assumptions.