When Bob Wills and his Texas Playboys sang the eponymous refrain in their 1940 classic “Time Changes Everything,” they were mostly telling the truth. Mostly. But the King of Western Swing had apparently never set foot in Schilo’s Delicatessen, a restaurant that has somehow managed to evade time’s inexorable march. My first experience with the unassuming German deli, located in the heart of downtown San Antonio, occurred at some point in the early seventies, when the now one-hundred-plus-year-old workaday eatery was a mere fiftysomething. I was no more than seven or eight, traveling with family for a weekend getaway or maybe tagging along with my dad, who was a lawyer by trade, to a State Bar convention. Memories from that trip—brief though it surely was—have stuck…