**Feature Request**
Brief title for your desired feature:
Add "In BOM" tick box to "Add new parameter" in new Schematic Lib and SPICE Symbol parts creation editors.
How would you like the feature to work?
When editing a symbol placed into a schematic, it is possible to "Add new parameter" and have it shown in the BOM by ticking the `In BOM` tick box.
When creating a new symbol it is possible to "Add new parameter" but there is no option to have it shown in the BOM because there is no `In BOM` tick box.
Why is this feature important to you?
Being able to add extra fields that are visible in the BOM into library parts, saves having to add these fields every time the symbol is to be placed into a new schematic.
It also saves forgetting to do add these fields to the first instance of every part placed in a schematic and then having to edit every instance in the schematic later (or having to do search and replace in the EasyEDA Source).