Add default tslint json

[bwnodak]

Thanks for the great custom rules. Unforunately I ran into some troubles when integrating them into a tslint-config package.

Using tslint-immutable in a tslint-config is problematic when using yarn. For example, a tslint-config package would add ./node_modules/tslint-immutable/rules to its rulesDirectory, but if the tslint-config package is installed into another project through yarn, the node_modules folder structure is flattened and the rulesDirectory path can't be found (because tslint-immutable is at the top level of the directory, rather than nested as it would be using npm).

Adding a default tslint-immutable.json to the project allows other tslint-configs to extend it, and not worry about missing rules.

[jonaskello]

Nice, I was not aware tslint could do this :-). Thanks for the contribution!