Insert row feature improvements

[bpasquer]

the behavior of the "insert row" feature is unsuitable.
Clicking on a row allows to insert a maximum of 3 rows consecutively while the number of insert could be unlimited.
Also, the limitation of inserting a single row at a time can make correction tasks very tedious (example when need to insert 70 rows). Ideally, this feature could work like in Excel, ie the number of row selected will correspond to the number of row inserted.