Add an option to disable sending email after crosperf finishes.

Test: Using this option, email is gone.
      Without this option, email is there.

PRESUBMIT=passed
R=shenhan,llozano,asharif
CC=dennisjeffrey
APPROVED=shenhan
DELTA=7  (6 added, 0 deleted, 1 changed)
OCL=65571-p2
RCL=65578-p2
RDATE=2013/01/31 11:20:46


P4 change: 42806548
3 files changed
tree: 7caca6188cb7049e42b73c4ca1155b31c61e2074
  1. .git5_specs/
  2. v14/