[Buildmonitor] Added the build data logging parts for BuildMonitor

[Buildmonitor] Added the build data logging parts for BuildMonitor

1. Added the build data logging parts in for BuildMonitor dashboard
   which can show the status of each build steps from beginning to the end

2. The related actions and python files are as below
  (1) gbs submit --------------- [job_submit.py]
  (2) [pre] packae build ------- [on OBS]
  (3) [pre] snapshot create ---- [job_pre_release_obs.py]
  (4) [pre] image creation  ---- [job_imager.py][job_post_imager.py]
  (5) SR accept or reject ------ [job_request.py]
  (6) [post] package build ----- [on OBS]
  (7) [post] snapshot creation - [job_create_snapshot.py]
  (8) [post] image creation ---- [job_imager.py]
  (9) Completed
  * pre : pre build / post : post build

3. The buildmonitor.py is the common interface file

Change-Id: Id97e8c5e131dc11713fdf58bbb0b794907cedaa1
Signed-off-by: SungHun Hwang <sh0924.hwang@samsung.com>