Re-wrote `search` method and changed search options. Needs more refactoring.

  * Removed the '--method', '--class', and '--module' options.
    They are all combined now in the '-m', '--map' option.
  * 'Search' changes:
    + use `File.foreach` to read file lines
    + add file name to output if file contains one of the search criteria
    + NOTE: this method is pretty messy. split it up and look for a
      better way to add the file name to output.