Improved .gitignore using gibo.
Improved .gitignore using gibo.

Change-Id: Iec8b269d344db6cc2adcb311e3a307f92c39b325
Reviewed-on: https://robertou.com/gerrit/27
Tested-by: Jenkins CI
Reviewed-by: Robert Ou <6265f2953535a346b7ba7418c552b02d288905ed@pioneers.berkeley.edu>

chuen0630/tenshi,cduck/tenshi,zentner-kyle/tenshi-old,hozhu123/tenshi,hozhu123/tenshi,SamboyKirk/tenshi,jessicakam/tenshi,hozhu123/tenshi,SamboyKirk/tenshi,abhishyantkhare/tenshi,cduck/tenshi,pioneers/tenshi,jarzofjam/tenshi,tobinsarah/tenshi,jarzofjam/tenshi,abhishyantkhare/tenshi,jarzofjam/tenshi,pioneers/tenshi,chuen0630/tenshi,cduck/tenshi,JaronArmiger/tenshi,cduck/tenshi,jessicakam/tenshi,hozhu123/tenshi,SamboyKirk/tenshi,JaronArmiger/tenshi,cduck/tenshi,JaronArmiger/tenshi,tobinsarah/tenshi,JaronArmiger/tenshi,tobinsarah/tenshi,jarzofjam/tenshi,SamboyKirk/tenshi,chuen0630/tenshi,jessicakam/tenshi,jarzofjam/tenshi,jarzofjam/tenshi,chuen0630/tenshi,hozhu123/tenshi,JaronArmiger/tenshi,JaronArmiger/tenshi,cduck/tenshi,tobinsarah/tenshi,jessicakam/tenshi,hozhu123/tenshi,SamboyKirk/tenshi,abhishyantkhare/tenshi,chuen0630/tenshi,jarzofjam/tenshi,pioneers/tenshi,pioneers/tenshi,pioneers/tenshi,SamboyKirk/tenshi,pioneers/tenshi,hozhu123/tenshi,tobinsarah/tenshi,abhishyantkhare/tenshi,jessicakam/tenshi,JaronArmiger/tenshi,zentner-kyle/tenshi-old,chuen0630/tenshi,pioneers/tenshi,cduck/tenshi,zentner-kyle/tenshi-old,abhishyantkhare/tenshi,SamboyKirk/tenshi,zentner-kyle/tenshi-old,zentner-kyle/tenshi-old,jessicakam/tenshi,chuen0630/tenshi,tobinsarah/tenshi,abhishyantkhare/tenshi,jessicakam/tenshi,abhishyantkhare/tenshi,tobinsarah/tenshi,zentner-kyle/tenshi-old