By Natalie Thomas ODESSA, Ukraine (Reuters) – A generation of Ukrainians who knew of war only from history books and the stories of their grandparents has been forced to prepare to fight, and some are choosing to do it with the partners they were building their lives with only weeks ago. In a training centre in the southern city of Odessa, young urban professionals who might normally be choosing where to meet friends for a coffee learn about handling weapons and applying emergency first aid to battlefield wounds. “Every person should know how to fight, how to make medicine, aid for your relati…