Fix for issue 286

[InAnYan]

Closes #286.

I added a test to DoiFetcherTest for DOI https://doi.org/10.1109/PERCOMW.2015.7133989.

The parsed title of the article should be:

Towards situation-aware adaptive workflows: SitOPT — A general purpose situation-aware workflow management system

But previously it was:

Towards situation-aware adaptive workflows: SitOPT — A general purpose situation-aware workflow management system

In order to make the cleanup, I added some code to the format method of the FieldContentFormatter. (Is that the right file for cleanup?).

Mandatory checks

• Change in CHANGELOG.md described in a way that is understandable for the average user (if applicable)
• Tests created for changes (if applicable)
• Manually tested changed features in running JabRef (always required)
• Screenshots added in PR description (for UI changes)
• Checked developer's documentation: Is the information available and up to date? If not, I outlined it in this pull request.
• 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.

[koppor]

Filed upstring at JabRef#11078, thus closing this one.