Fixed #231 - add libraries to about dialog

BudgetMasterClient/src/main/resources/de/deadlocker8/budgetmaster/languages/_de.properties

@@ -4,7 +4,7 @@ version.code=13
 version.name=1.8.0_alpha
 version.date=07.11.17
 author=Robert Goldmann
-credits=Länderflaggen von Freepik auf https://www.flaticon.com\nVerwendete Schriftarten: OpenSans
+credits=Länderflaggen von Freepik auf https://www.flaticon.com\nVerwendete Schriftarten: OpenSans\nVerwendete Bibliotheken:\ngson 2.8.1\njoda-time 2.9.7\nitextpdf 5.0.6\nlaunch4j-maven-plugin 1.7.21\nspark-core 2.5.4\nslf4j 1.7.21\nmysql-connector 6.0.5\njunit 4.12
 
 folder=Deadlocker/BudgetMaster
 roadmap.url=https://deadlocker.thecodelabs.de/roadmap/php/index.php?id=1

BudgetMasterClient/src/main/resources/de/deadlocker8/budgetmaster/languages/_en.properties

@@ -4,7 +4,7 @@ version.code=13
 version.name=1.8.0_alpha
 version.date=07.11.17
 author=Robert Goldmann
-credits=Flags by Freepik on https://www.flaticon.com\nFonts used: OpenSans
+credits=Flags by Freepik on https://www.flaticon.com\nFonts used: OpenSans\nLibraries used:\ngson 2.8.1\njoda-time 2.9.7\nitextpdf 5.0.6\nlaunch4j-maven-plugin 1.7.21\nspark-core 2.5.4\nslf4j 1.7.21\nmysql-connector 6.0.5\njunit 4.12
 
 folder=Deadlocker/BudgetMaster
 roadmap.url=https://deadlocker.thecodelabs.de/roadmap/php/index.php?id=2