Fix adding empty string

[JLLeitschuh]

Closes #207

[codecov-io]

Current coverage is 48.56%

Merging #210 into master will increase coverage by +0.28% as of 29f7995

@@            master    #210   diff @@
======================================
  Files          104     104       
  Stmts         2504    2504       
  Branches       253     253       
  Methods          0       0       
======================================
+ Hit           1209    1216     +7
- Partial         46      47     +1
+ Missed        1249    1241     -8

Review entire Coverage Diff as of 29f7995

---

Uncovered Suggestions

1. +0.48% via .../MainWindowView.java#84...95
2. +0.44% via .../ExceptionAlert.java#95...105
3. +0.40% via ...InputSocketView.java#36...45
4. See 7 more...

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