Changed some i18n and icon names.
Added new actions for new effects (Animation, TimedEffect...)
Minor changes.
Added methods in EffectsIndex and new attributes in FieldName
Added widget for show a timeline.
Added widgets that contain a effect.
Added layout that contains a TrackEffect.
Added widget to show the edition of animations.
Changed actions of effects for not to use the values of TrackLayout widget as args.
Also corrected some minor typos.
Merge pull request #716 from gorco/EditAnimationWidget

Edit animation widget