text: Title: [Datalab new issue type] detect ID columns in features
  Body: [New Datalab issue type](https://docs.cleanlab.ai/master/cleanlab/datalab/guide/custom_issue_manager.html) called something like `identifier_column` that checks whether `features` contains a column that is entirely sequential integers.
  
  That is check whether there exists a column `i` in `features` such that `set(features[:,i]) = set(c, c+1, ..., c+n)` for some integer `c`, where `n` = num-rows of `features`. Note we don't consider the ordering of the column in case the dataset was pre-shuffled.
  
  If the condition is met, then we say this dataset has the `identifier_column` issue (similar to the non-iid issue). The overall issue-summary-score can simply be binary = 0 if the dataset has this issue = 1 otherwise.
  
  In this case the `info` attribute of Datalab should specify which column(s) seem like the identifier.
  
  `datalab.issues` does not need to reflect this issue-type at all, since it is not something related to the rows of the dataset.
  
  
  Motivation: ID columns are common in datasets, but generally should be left out of ML modeling or they risk harming the results.