ergonomics in contingencies editor : bind keys + fix save after rename

[miovd]

• ContingencyStoreEditor
  • bind "Delete" key to remove a Contingency or a ContingencyElement
  • bind "F2" key to rename a Contingency
  • after renaming a Contingency, allow the user to save if the new name is different or non null

[murgeyseb]

The functional part is ok for me.
It could have been great to prevent renaming (i.e. clicking on OK button) when the name is empty or equal to the old name, but it does not seem to be that easy to implement based on that implementation. At least, there is no update of the name if empty string is provided.

[murgeyseb]

Ok for me