add FsCheck. (#2)
add Result type. (#2)
add Result.fold. (#2)
fix typo. (#2)
add Result.foldFailure. (#2)
add Result.bind/Result.bindFailure. (#2)
refactor tests. (#2)
add Result.exists/existsFailure. (#2)
add Result.forall/forallFailure. (#2)
add Result.get/getFailure. (#2)
add Result.isSuccess/isFailure. (#2)
add Result.iter/iterFailure. (#2)
add Result.map/mapFailure. (#2)
Merge pull request #5 from bleis-tift/result-type

#2