Explain 'colors' section and its variables, used for The variables for
customizing the colors used in the output for the 'report', 'top' and
'annotate' in the TUI, those are:

'top', 'medium', 'normal', 'selected',
'jump_arrows', 'addr' and 'root'.
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1452253193-30502-2-git-send-email-treeze.taeung@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>