Fixed PHP-685: wtimeout option is not supported per-query

We simply never checked for the option in the options array.
Now we'll fall back on the MongoCollection->wtimeout (which inherits the
wtimeout from MongoDB->wtimeout, which is set by the connection string,
or defaults to PHP_MONGO_DEFAULT_WTIMEOUT)
Tweaked log messages and fixed all remaining test cases.
Fixed test case - I can actually replicate that fast.

Setting w=7 as we do that for some other tests to test timeouts as well (f.e.
in replicaset/bug00569-004.phpt).
Merged pull request #290