Change behavior for adding templates (on atoms bonds)

**Acceptance criteria:**
* If two structures are merged on bond, the bond order should be kept from the existing structure on canvas.
* Ketcher should preserve an existing bond type if user adds a first structure and tries to merge a new structure taken from template library or from paste buffer ( Ctrl+V)
* Add configuration parameter in settings for aromaticity behavior. Aromatic bonds re-calculation should be turned off by default