macro to deal with try-catch for either monad

[shmish111]

Would it be possible to add the following to the either namespace, I use it all the time:

(defmacro try-either
  "try to evalute the body and return the result as a right, if an exception is throw return the exception as a left"
  [& body]
  `(try (right ~@body)
        (catch Exception e# (left e#))))

[ghost]

Makes sense, feel free to open a pull request!

[shmish111]

created #155