Update projects.lang

Add Link element on elements page
Update element.php

add feature: join element from element page
Update project.class.php

Add feature to add element in elements page of a project
Fix: [ bug #855 ] Holiday approval email in French
Update ChangeLog
Fix: [ bug #855 ] Holiday approval email in French
Fixed a bug when showing users to define holidays
Style improvement
Added DurationDays string to the table
Corrected translation key
Corrected ca_ES translations
Translations made by Juanjo Menent (simnandez)
Merge remote-tracking branch 'origin/3.3' into develop

Conflicts:
	htdocs/holiday/fiche.php
Merge pull request #899 from defrance69/patch-2

Update element.php
Merge pull request #898 from defrance69/patch-1

Update projects.lang
Merge pull request #900 from defrance69/patch-3

Update project.class.php
Merge pull request #901 from marcosgdf/develop

Holidays module improvements
Add table extrafield for commande fournisseur...
Seems this module work as separate from order but config is missing. Try
to create a new one.