Allow reload of lsyncd config independent of slave change check

Right now, a new lsyncd config - ```lsyncd.conf.lua``` is generated only when new slaves have been added/removed from the load balancer. However, it is possible that there is a change in the original config template - ```lsyncd.conf.lua.template``` itself or a change in the values for certain parameters in the ```config.php``` file (app config) in which case we may want to do a lsyncd config reload independently.

This pull request adds a new file ```reload_config.php``` (open to a better name) that can be used for this purpose.

    # Generates a new data/lsyncd.conf.lua file 
    php reload_config.php
    # Generates a new lsyncd conf file & restarts the daemon
    php reload_config.php --restart

Have also refactored out three methods in ```utilities.php```:

    getSlaves()
    setSlaves()
    reloadConfig()