secret-handshake: Use 3 and 19, not 9 and "11001"
secret-handshake: Use 3 and 19, not 9 and "11001"

We'd like to use 3 and 19 to match up with what's in the test cases
already used by most languages. We also do not want to do binary to
integer conversions, by discussion in #159.

This covers most tasks in #335, though I would probably still leave #335
open because explicit discussion of numbers larger than 11111 has not
been added.

rpottsoh/x-common,exercism/x-common,jmluy/x-common,petertseng/x-common,jmluy/x-common,Vankog/problem-specifications,ErikSchierboom/x-common,kgengler/x-common,Vankog/problem-specifications,kgengler/x-common,jmluy/x-common,ErikSchierboom/x-common,rpottsoh/x-common,exercism/x-common,petertseng/x-common