Symmetric extrude with respect to the workplane

[adam-urbanczyk]

Added additional parameter (both=Flase by default) to the extrude method
which allows to symmetrically extrude with respect to he current
workplane

[coveralls]

Coverage decreased (-10.9%) to 74.595% when pulling 32160d1 on adam-urbanczyk:master into bcea03d on dcowden:master.

[adam-urbanczyk]

Not sure if you accept PRs, but would be nice to also have symmetric extrude

[jmwright]

Thanks @adam-urbanczyk we do accept PRs. Would you be able to add a test case for symmetric extrusion, please?

[coveralls]

Coverage decreased (-10.8%) to 74.696% when pulling 58683d0 on adam-urbanczyk:master into bcea03d on dcowden:master.

[adam-urbanczyk]

Does it look better now?

[jmwright]

Yes, thanks. The only other thing that I would suggest would be to add an explicit 0 after the decimal places in the floats for consistency. Other than that it's ready to merge.

[jmwright]

By consistency I mean that we've used trailing 0s throughout the codebase, unless I've overlooked something.

[dcowden]

This looks ok to me
@jmwright are you comfortable that the coveage issue is unrelated to the changes in this PR? if so I'll merge it.

[jmwright]

@dcowden I'm fine with that. I suspect that the Coveralls issue is separate. I'd say go ahead and merge.

[dcowden]

@adam-urbanczyk thanks for the contribution! Merged.

[jmwright]

@adam-urbanczyk Agreed. We appreciate the help.