Make comment generic for all files

htdocs/langs/en_US/admin.lang

-# Dolibarr language file - en_US - admin
+# Dolibarr language file - Source file is en_US - admin
 CHARSET=UTF-8
 Foundation=Foundation
 Version=Version

htdocs/langs/en_US/agenda.lang

-# Dolibarr language file - en_US - agenda 
+# Dolibarr language file - Source file is en_US - agenda 
 CHARSET=UTF-8
 Actions=Events
 ActionsArea=Events area (Actions and tasks)

htdocs/langs/en_US/banks.lang

-# Dolibarr language file - en_US - banks
+# Dolibarr language file - Source file is en_US - banks
 CHARSET=UTF-8
 Bank=Bank
 Banks=Banks

htdocs/langs/en_US/bills.lang

-# Dolibarr language file - en_US - bills
+# Dolibarr language file - Source file is en_US - bills
 CHARSET=UTF-8
 Bill=Invoice
 Bills=Invoices

htdocs/langs/en_US/bookmarks.lang

-# Dolibarr language file - en_US - marque pages
+# Dolibarr language file - Source file is en_US - marque pages
 CHARSET=UTF-8
 AddThisPageToBookmarks=Add this page to bookmarks
 

htdocs/langs/en_US/boxes.lang

-# Dolibarr language file - en_US - boxes
+# Dolibarr language file - Source file is en_US - boxes
 CHARSET=UTF-8
 BoxLastRssInfos=Rss information
 BoxLastProducts=Last %s products/services

htdocs/langs/en_US/cashdesk.lang

-# Language file - en_US - cashdesk
+# Language file - Source file is en_US - cashdesk
 CHARSET=UTF-8
 CashDeskMenu=Point of sale
 CashDesk=Point of sale

htdocs/langs/en_US/categories.lang

-# Dolibarr language file - en_US - categories
+# Dolibarr language file - Source file is en_US - categories
 CHARSET=UTF-8
 Category=Category
 Categories=Categories

htdocs/langs/en_US/commercial.lang

-# Dolibarr language file - en_US - commercial
+# Dolibarr language file - Source file is en_US - commercial
 CHARSET=UTF-8
 Commercial=Commercial
 CommercialArea=Commercial area

htdocs/langs/en_US/companies.lang

-# Dolibarr language file - en_US - companies
+# Dolibarr language file - Source file is en_US - companies
 CHARSET=UTF-8
 ErrorCompanyNameAlreadyExists=Company name %s already exists. Choose another one.
 ErrorPrefixAlreadyExists=Prefix %s already exists. Choose another one.

htdocs/langs/en_US/compta.lang

-# Dolibarr language file - en_US - compta
+# Dolibarr language file - Source file is en_US - compta
 CHARSET=UTF-8
 Accountancy=Accountancy
 AccountancyCard=Accountancy card

htdocs/langs/en_US/contracts.lang

-# Dolibarr language file - en_US - contracts
+# Dolibarr language file - Source file is en_US - contracts
 CHARSET=UTF-8
 ContractsArea=Contracts area
 ListOfContracts=List of contracts

htdocs/langs/en_US/cron.lang

-# Dolibarr language file - en_US - cron
+# Dolibarr language file - Source file is en_US - cron
 CHARSET=UTF-8
 Module2310Name=Cron
 Module2310Desc=Scheduled task management

htdocs/langs/en_US/deliveries.lang

-# Dolibarr language file - en_US - deliveries
+# Dolibarr language file - Source file is en_US - deliveries
 CHARSET=UTF-8
 Delivery=Delivery
 Deliveries=Deliveries

htdocs/langs/en_US/dict.lang

-# Dolibarr language file - en_US - dict
+# Dolibarr language file - Source file is en_US - dict
 CHARSET=UTF-8
 CountryFR=France
 CountryBE=Belgium

htdocs/langs/en_US/donations.lang

-# Dolibarr language file - en_US - donations
+# Dolibarr language file - Source file is en_US - donations
 CHARSET=UTF-8
 Donation=Donation
 Donations=Donations

htdocs/langs/en_US/ecm.lang

-# Dolibarr language file - en_US - ecm
+# Dolibarr language file - Source file is en_US - ecm
 CHARSET=UTF-8
 MenuECM=Documents
 DocsMine=My documents

htdocs/langs/en_US/errors.lang

-# Dolibarr language file - en_US - errors
+# Dolibarr language file - Source file is en_US - errors
 CHARSET=UTF-8
 
 # No errors

htdocs/langs/en_US/exports.lang

-# Dolibarr language file - en_US - exports
+# Dolibarr language file - Source file is en_US - exports
 CHARSET=UTF-8
 ExportsArea=Exports area
 ImportArea=Import area

htdocs/langs/en_US/externalsite.lang

-# Dolibarr language file - en_US - externalsite
+# Dolibarr language file - Source file is en_US - externalsite
 CHARSET=UTF-8
 ExternalSiteSetup=Setup link to external website
 ExternalSiteURL=External Site URL