US - compare and cache eTags

[benoitdm-oslandia]

As editor, I want to save my modifications on the latest version of the data in order to have an integrated collection and obtain the latest version efficiently

• [ ] #72
• [ ] #81
• [ ] #82
• [x] #73
• [ ] #74
• [ ] #142
• [ ] #77
• [x] #43
• [x] #51
• [x] #75

[benoitdm-oslandia]

marked this issue as related to #9

[benoitdm-oslandia]

marked this issue as related to #80

[benoitdm-oslandia]

marked this issue as related to #81

[benoitdm-oslandia]

marked this issue as related to #77

[benoitdm-oslandia]

marked this issue as related to #76

[benoitdm-oslandia]

marked this issue as related to #74

[benoitdm-oslandia]

marked this issue as related to #73

[benoitdm-oslandia]

marked this issue as related to #72

[benoitdm-oslandia]

marked this issue as related to #50

[benoitdm-oslandia]

marked this issue as related to #89