add boolean help

ChangeLog

pom.xml

src/main/java/fr/ill/ics/bridge/events/ChatEvent.java

src/main/java/fr/ill/ics/core/property/Property.java

src/main/java/fr/ill/ics/core/property/PropertyManager.java

src/main/java/fr/ill/ics/core/property/StringProperty.java

...va/fr/ill/ics/nscclient/dataprovider/ServantDatabase.java

...ll/ics/nscclient/dataprovider/ServantManagerAccessor.java

...fr/ill/ics/nscclient/serverconnection/ServerInstance.java

src/main/java/fr/ill/ics/util/ConfigManager.java