Revert #14 for Julia 0.6

[saschatimme]

This reverts #14 for Julia 0.6 to adress #18. This is not really satisfactory, but I would appreciate if we could get this merged for the time until we all reach the 0.7 happy land.

[coveralls]

Coverage decreased (-1.02%) to 98.613% when pulling 1c245d4 on revert-#14 into 8b2b1a0 on master.

[codecov-io]

Codecov Report

Merging #25 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master      #25   +/-   ##
=======================================
  Coverage   99.02%   99.02%           
=======================================
  Files          15       15           
  Lines         721      721           
=======================================
  Hits          714      714           
  Misses          7        7

Impacted Files	Coverage Δ
src/mono.jl	100% <100%> (ø)	⬆️

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[saschatimme]

@blegat I was a little bit too tired yesterday and forgot to disable all of the corresponding testcases for 0.6 but not everything works.

This bug is really strange, since it isn't even called in my code (otherwise there would have been a stackoverflow), nonetheless it crashes the compiler 🤷‍♂️

[blegat]

Do you mean you get this crash ?