Added missing copyright notice
Added a getValue utility function

util.getValue() can parse a parameter ID in order to return
elements of arrays.
Added a parseDimensions utility function

Parses a type string ('integer[2][][3]') and returns a list of
the array dimensions. This function might become deprecated soon.
Added a nextArray function to generators

Can create arbitrarily sized arrays using any normal parameter.
Array parameters will probably be handled in a different way, but
this function might still be useful in the future. AFAIK, InPUT4j
supports the creation of arbitrary arrays of regular parameters.
Added ParamArray and getParameter factory function

ParamArray is a special type of parameter that represents
an array of some type as defined by another parameter.
Added ArrayGenerator
Generators automatically use any fixed value
Removed __getValue from DesignSpace
DesignSpace can now generate arrays

Had to fix some issues:
- ParamArray is probably not supposed to inherit from Param.
- Fixed a silly bug in ParamArray (forgot to return a value from
    __getattr__).
- Individual generators have to ask their super class for a
    fixed value. Checking in generators.nextValue didn't play
    well with arrays.
A Design with an array can now be created

This functionality existed earlier as well, but accessing the
individual elements relies on util.getValue.

Also fixed a minor bug. The ArrayGenerator didn't default to a
size of 1 for any zero-sized array.