2.5.1: changed back to wait, as sleeps can add up quickly

and then imgult will take forever to complete

2.5.0: OVERLOAD PROTECTION ENCABULATOR!

limit active processes to 9

2.4.4

add an extra check for egrep

2.4.3: sleep is better than wait if comp is really fast

otherwise it may not have time to finish

2.4.2

finally!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

2.4.1

don't exit if any of the optimizers are running

svgo

2.4.0

welcome svgo!

2.3.3

whitespace cleaning

2.3.2

wait > sleep

2.3.1

now works on large scale deploys