create directories for each layer of the development assurance process

Updated based on meeting discussion,  Anne-Perrine and Alexandre comments

This reverts commit 13d59d12.

This reverts commit 7e0b5486.

First draft of the specification at AV level (step 1)

- 1st sheet : remarks
- 2nd sheet :  interfaces issues

document with remarks on specification documents
- 1 sheet on document "OP oriented"
- 1 continuing remarks on last version
- 1 sheet with analysis of interfaces : inconcistencies and missing
elements

This reverts commit b5bcb8fa80ac69a350455f930cf5f57397829812.

system modelization  with verification of interfaces

in particular "e.g " into e.g. " and "i.e " into "i.e. "