No repeal, modification or waiver of requirements.

Nothing contained in this chapter shall be held to repeal or modify or waive any existing requirement or statute of limitations which is applicable to these causes of action but, on the contrary, shall be held to be additional requirements to the rights to maintain such action; nor shall anything herein contained be held to modify any existing rule of law relative to the question of contributory negligence, nor to impose upon the town, its officers and employees and/or any of its improvement districts any greater duty or obligations than that it shall keep its streets, sidewalks and public places in a reasonably safe condition for public use and travel.