Better error outputs for convertor maybe?

[hunterhector]

Would it be possible to make the error message more specific? We would like to know which particular directory is not a directory, while we probably don't care much about the parameter name.

For example:

java.lang.IllegalArgumentException: Parameter 'directory' is not a directory at org.apache.commons.io.FileUtils.validateListFilesParameters(FileUtils.java:545) at org.apache.commons.io.FileUtils.listFiles(FileUtils.java:521) at org.apache.commons.io.FileUtils.listFiles(FileUtils.java:691) at evmeval.TokenFileMaker.createFiles(TokenFileMaker.java:206) at evmeval.TokenFileMaker.main(TokenFileMaker.java:325) [ERROR] Stopped due to an error.