Merge pull request #115 from babs/code-refactoring-trans-fr

Updated fr_FR translation
Fixed a bug when creating/editing enums.
Enabled FK relationship removal. Removing the relatinships the fk's are
removed too. More test needed. (issue #118)
Fixed bug related to the relationship semantics (issue #121)

Fixed some memory leaks related to operation list
Fixed a bug when creating Views with WERE statement.
class RelacionamentoWidget refactored to RelationshipWidget. Pending
comment translation.
RelationshipWidget class refactoring done.
class RestricaoWidget refactored to ConstraintWidget. Pending comment
translation.
ConstraintWidget class refactoring done.
class SeletorObjetoWidget refactored to ObjectSelectorWidget.
Class SequenciaWidget refactored to SequenceWidget.
class TabelaObjetosWidget refactored to ObjectTableWidget. Pending
comment translation.
ObjectTableWidget signal refactoring.
ObjectTableWidget class refactoring checkpoint. Pending comment
translation.
ObjectTableWidget class refactoring checkpoint. Pending .cpp comment
translation.

Global message box instance removed form main window.
ObjectTableWidget class refactoring done.
Class TabelaWidget refactored to TableWidget. Pending comment
translation.
Updated fr_FR