Refactor JavaScript for test environment setup
Refactor PHP-535 test and relocate to replicaset group

Changed test to require the RS environment and connect to the appropriate DSN instead of a hard-coded host and port. Also reduced test complexity, since this really only needs to assert successful command execution and routing.
Update cleantests.sh for new test directories

Previous script would have removed PHP scripts in the utils directory. Changed to explicitly process test group directories.
PHP-738: Support tagged replica set members
PHP-738: Ensure that RS node config options get saved
PHP-738: Fix legacy RS log tests for replica set tags
There is no need to kill it completely, just step it down

This reduces the crazy amount of time the failover tests require
Merged Pull Request #390

# By Jeremy Mikola (6) and Hannes Magnusson (1)
* pull-request/390:
  There is no need to kill it completely, just step it down
  PHP-738: Fix legacy RS log tests for replica set tags
  PHP-738: Ensure that RS node config options get saved
  PHP-738: Support tagged replica set members
  Update cleantests.sh for new test directories
  Refactor PHP-535 test and relocate to replicaset group
  Refactor JavaScript for test environment setup
Couple of new failover tests
Merged Pull Request #393

* pull-request/393:
  Couple of new failover tests
Fixed PHP-741: Passive replicaset members (priority=0) not used for secondary reads
Configure one of the servers to never become primary (passive secondary)
Fixed test after PHP-741
Merged pull request #392
Fix a fragile test

Write to majority, but still sleep for one second, in case we hit the
server that didn't get the write :/
Merged pull request #394