Fix issue 429

[desperadomzc]

Modify the method printUage() in file: src/main/java/org/jabref/cli/JabRefCLI.java

Make the import and export format of cli output consistent.

Fixes koppor#429

Compulsory checks

Beta Give feedback

1. Change in CHANGELOG.md described in a way that is understandable for the average user (if applicable)
2. Tests created for changes (if applicable)
3. Manually tested changed features in running JabRef (always required)
4. Screenshots added in PR description (for UI changes)
5. Checked developer's documentation: Is the information available and up to date? If not, I outlined it in this pull request.
6. Checked documentation: Is the information available and up to date? If not, I created an issue at https://github.com/JabRef/user-documentation/issues or, even better, I submitted a pull request to the documentation repository.

[Siedlerchr]

No need to close or reoopen the PR! Every new commit & push will udpate the PR automatically!

[ThiloteE]

Please be aware, everytime you open and close a pull-request, people subscribed to JabRef's GitHub repository will receive e-mails. Please avoid (unintended) spam. This is how my inbox looks like:

[koppor]

The PR was closed and a follow-up PR #9937 was opened.

Note that everyone having access to the repository where the pull request comes from, can update the pull request.

[desperadomzc]

OMG, Sorry about the spams. I apologize.