erl VM flags

Added "+sbwt very_long +swt very_low"
Update client connection pool to mirror benchmark's MySQL pool limit of 5k

Erlang is highly concurrent, so under load, especially to a remote system it is quite conceivable to utilize very high numbers of connections if available.
Added VM flags "+K true +sbwt very_long +swt very_low"
Update limits

Update client connection pool to 5k, to mirror test harness 5k connlimit on my.cnf

Update spawned Cowboy to 5k to match what Elli does and increase throughput instead of spawning more listeners dynamically (which is more expensive than a simple Erlang process.)
Merge branch 'master' of https://github.com/moxford/FrameworkBenchmarks into moxford-master
Removed flag +K true since this lowered the performance of the tests