provide options to append numbers and special chars

[dpalic]

It would be great to have the option to control how and where to add numbers and symbols
E.g. it would be great to have an option (e.g. config class) in which you can say:

• add following count of number as Set of Integers
• add following count of symbols for symbols like #!?-_ and so on
• preferSymbols at end of Word
• use Upper-Case / Lower-Case for new words

[maximeroussy]

I'm not sure if numbers or symbols would fit the original intent of the library. Do you have a particular use case in mind?