Revert "update typescript definition ( subscribe callback -= monitor )"

This reverts commit d92f600ee3af2133f1de978ecde0217a206d00cf.
Revert "remove subscribe callback third argument ( monitor )"

This reverts commit 6f480d568ffe8dbcd54cfd79bc84bfa15c1d7a67.
revert calling cancel on monitor ( in subscribe )

we cannot cancel because we are surfacing the Monitor instance to the
user ( by passing it through the callback ). It was a good idea to
remove this ( from a GC point of view ) but syncify is using it. I will
take a look at syncify to see if I can avoid using the Monitor directly.
version.coffee++
2.3.2