Changes Conversation#id for conversationId avoiding conflict with ModelComponent#id.
Adds Conversation actions.
Adds ShowText prefab panel.
TriggerConversationExecutor prioritizes in the target first.
Avoid creating new String objects in the update method.
Small improvements.
Merge pull request #745 from RotaruDan/textFunctionality

Adds ShowTextPanel.
Fixed minor bugs in Windows.
i18n and skin changes.
Added new actions with behaviors.
Changed the widget used to representat variables.
Minor changes in PositionedHiddenPanel.class and IconWithPanel.class
Added widgets for select variables and show it, allowing "and" and "or" conditions.
Now the ChangeVariablePanel and ConditionalPanel use the new variables widgets
Minor changes in prefab panels.
Minor skin changes