fix(ihm): prevent multisynchro (refs #4468)

Add a constant in window and use event system to prevent mutiple
synchronize
feat(ihm): Fix ellipsis on left on docid (refs #4471)
fix(download): update saveFiles (refs #4470)

Refactoring of fileManager to be more resilient

Add callback to handle save and download errors
Merge pull request #60 from cbonnissent/1.6.15

1.6.15 (closes #4468, closes #4471, closes #4470)