SCons: Separately label the global non-sticky options.

SCons: Separately label the global non-sticky options.

The global sticky options were being printed with a heading, and then the
global nonsticky options were being printed immediately after them without a
heading. Because the two lists ran together and the first had its own heading,
it looked like -all- those options where sticky even though some of them
aren't. This change adds a label to the second list so it's clear they're
different.