XWIKI-7571: Improve maintenance and stability of IRC Bot Application

* Add gitignore

.gitignore

+# Build
+target
+target-eclipse
+
+# IDEA
+*.iml
+*.ipr
+*.iws
+.idea
+atlassian-ide-plugin.xml
+
+# Eclipse
+.classpath
+.project
+.settings
+.checkstyle
+.fbprefs
+bin
+# Automatically generated by WTP
+/*/src/main/java/META-INF/
+/*/*/src/main/java/META-INF/
+/*/*/*/src/main/java/META-INF/
+/*/*/*/*/src/main/java/META-INF/
+/*/*/*/*/*/src/main/java/META-INF/
+/*/*/*/*/*/*/src/main/java/META-INF/
+/*/src/META-INF/
+/*/*/src/META-INF/
+/*/*/*/src/META-INF/
+/*/*/*/*/src/META-INF/
+/*/*/*/*/*/src/META-INF/
+/*/*/*/*/*/*/src/META-INF/
+
+# NetBeans
+nbproject
+
+# Other
+*.log.*
+*.log
+.sonar-ide.properties
+.clover