The pull request included some changes that were neither accidental nor
unintentional, so only a subset of the changes from pull request #869
submitted by klorpa were manually applied.
behaviour -> behavior
speach -> speech
knowlege -> knowledge
incrments -> increments
stethscope -> stethoscope
staiway -> stairway
arifact -> artifact
extracing -> extracting
The uses of "iff" were left alone.
Close#869
If an old port is resurrected to work with current version code, its files
can be relocated to the appropriate sys or win folder as required.
In the meantime, the burden of upkeep can be avoided for the stuff in the
outdated folder for now.