Update PV defaults, generator inputs bug fix, Float64 arg types to Real

• Update PV defaults to tilt=10 for rooftop, tilt = abs(lat) for ground mount, azimuth = 180 for northern lats, azimuth = 0 for southern lats.
• bug fix for Generator inputs to allow for time_steps_per_hour > 1
• change various Float64 argument types to Real to allow integers too