Add a dynamic string collections class

The class represents a collection of string collections accessible via a
string key. When a requested key does not exist the collection should try
to get a matching collection from its string source and cache the result.
Add methods that helps getting random dates

Extension methods Date and DateBetween of Random which return random
dates.
Add FileStringSource and CsvDestination

- The file string source reads strings from text files in a specific
  directory. The key must match a text file name excluding the .txt
  extension.

- The Csv destination writes the fake data to a CSV file using a specific
  separator.
Add console app to test the API
Implement String extension method to Random

The method would allow us to call random.String("Foo") to get a random
string from the "Foo" collection.
Add string files for common swedish names

Now we can implement string methods which return random names.
Add function for swedish personal id numbers

The birth date range, sex and output format can be specified via
arguments.
Refactor: move csv destination to own project

We do this to remove destinations from the main project. A user can select
the destination they want by referencing the dll.
Add Sql destination

The sql destination loads the generated fake data into an SQL database.
Refactor: Let destination load return collection

Sometimes it is interesting to let the destination modify items, e.g. in
the case of an SQL destination that sets an auto increment id column.
Later loads can then use the information returned to set relations.
Add ItemFrom extension method to Random

The method should get a random element from a specified enumerable.