Move substituion logger from class method to controllers
Fix #1414 Add immediate thumbnail substitution after success download
Fix CS
Use temporary file system
Fix & enhance unit tests
Adressed @romainneutron 's comments
Merge pull request #562 from nlegoff/fix_1414

[3.8] Fix 1414 Add immediate thumbnail substitution after success download
Fix #1430 : Use strict standards, declare the method static
Fix #1422 : logfiles contain duplicates log messages
Merge pull request #603 from romainneutron/fix-1422

Fix 1422 : logfiles contain duplicates log messages
Merge pull request #601 from romainneutron/fix-1430

[3.8] Use strict standards for task::getName method
Fix #1424 : Editing a story don't work
Fix #1427 stamp background
Merge pull request #605 from romainneutron/fix-1424

[3.8] Fix 1424 : story editing don't work
Fix #1426 : stamp text position
Fix #1425 Zindex issue
Fix #1421 Overflow issue
Fix #1420 Fix wording
Merge pull request #606 from romainneutron/fix-1427

[3.8] Fix 1427
Merge pull request #607 from romainneutron/fix-1426

[3.8] Fix stamp text position