Create "modules" directory inside "var" for data

[PierreRambaud]

Questions	Answers
Branch?	develop
Description?	We should have a directory where modules can store their files instead of continue putting them inside the modules directory.
Type?	improvement
Category?	CO
BC breaks?	no
Deprecations?	no
How to test?	No need QA.
Possible impacts?	Please indicate what parts of the software we need to check to make sure everything is alright.

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This change is 

[prestonBot]

Hi, thanks for this contribution!

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[Progi1984]

Thanks @PierreRambaud