Exp.bins is not used, deleted a comment about it
calculate.all() not ready, now it throws an error
Wrote gauss(), helper for calculate.distributed()

Normalized Gaussian function
map function, applys f to each other arg
combinations returns a tab when arg is tab of tabs

This change makes it much easier to deal with an unknown number of
aguments by keeping everything in tables, but it can still be used the
old way when given multiple arguments.  Updated the function in
utility/helpers.lua and its use in generation/spectragen.lua.
added a comment to explain combinations
genSets returns parameters given distributions

takes some information from settings.lua.
Wrote calculate.distributed()
fixed typo in genSets()
put a proper error level in calculate.single()
calc distrib works, using helpers product and find
added a scale method to spectrum
calc distrib now checks for param constraints
added param constraints to exp table