What considerations do I need when wiring a string of light bulbs in parallel?
to get the needed amp rating for the wiring and fuse you take the wattage of the bulbs divide by the voltage and multiply by number of bulbs. 

so 15 75W bulbs means 75W/230V*15 ~ 5 amps. this is much less than would need a dedicated circuit. (it's the same as a 1125W appliance).