replace trailing whitespace with blackslash in README.md

As an alternative to the markdown trailing whitespace as a line
break, we use a trailing blackslash as a markdown line break.

2000/anderson/README.md

@@ -1,9 +1,9 @@
 # Best Use of Flags
 
-Glyn Anderson  
-Jl. Raya Serang KM 18.2  
-Desa Bojong  
-Cikupa, Tangerang, 15710  
+Glyn Anderson\
+Jl. Raya Serang KM 18.2\
+Desa Bojong\
+Cikupa, Tangerang, 15710\
 Indonesia