No error message for non-existant commits

[MohammadEglil]

I used to get error messages when I would execute the command echo <commit> | ~/lookup/getValues c2dat for a commit which does not exist. But now I just get nothing as an output whereas I used to get no map for c2dat some time ago

[audrism]

showCnt gives errors while getValues does not when fed sha1 for an object that is not in the database.
Perhaps this should be an option for both.

[loconous]

Opened PR for change on error message for getValues.
See PR here: https://bitbucket.org/swsc/lookup/pull-requests/7

[loconous]

This PR is merged. @MohammadEglil please verify and resolve issue at your convenience. Thanks!

[loconous]

@MohammadEglil have you been able to verify if this fixed your issue? If so, please resolve at your convenience.
Also, as an FYI, see #45. This would allow to suppress this messages with a flag, but it is currently not implemented.