process: Support fixed oom for app via Private config

process: Support fixed oom for app via Private config

This patch includes
  - Parsing config from Private Section (config-parser.c/h)
  - Elimination of old style fixed oom config (proc.conf, README)
  - Replacement of oom_fixed_app_list using fixed_app_list
    (a.k.a. an hashtable which manages all apps in the Private Section)

Difference between old style fixed oom config and the current one
  - old style: Add app name directly in the common configuration file
  - the current style: Add app name in the Private Section (xxx.conf.d/yyy.conf)
    That is, any developer can add new configurations with making
	private conf files.

Change-Id: I21abd58002ce48ce66ff203bececa7d573443a39
Signed-off-by: Unsung Lee <unsung.lee@samsung.com>