Complete CBRAIN Wiki (redmine 7155)

[prioux]

The online wiki is not complete for the moment. Some files are just placeholders:

./Acknowledgment.md ./interface-guides/admin-guides/Regular-Maintenance.md ./placeholder.md ./programmer-guides/External-APIs.md ./programmer-guides/Logging-And-Provenance.md ./programmer-guides/MetaData.md ./programmer-guides/userfile/Userfile-DataProviders.md ./programmer-guides/userfile/Userfile-Loaders.md ./programmer-guides/userfile/Userfile-Programmer-Guide.md ./programmer-guides/userfile/Userfile-Viewers.md ./setup-guide/Communications.md ./setup-guide/Development-Hints.md ./setup-guide/FAQ.md ./setup-guide/Production-Hints.md

(Original issue by Natacha)