resource: Add disk and network resource driver

resource: Add disk and network resource driver

Add disk and network resource driver to provide monitoring data.

1. Add disk resource driver to provide the disk bandwidth
   and usage with following resource attributes:
- DISK_ATTR_NAME indicates the disk device name
- DISK_ATTR_READ_PER_SEC indicates read bandwidth of specific block like zram0
- DISK_ATTR_WRITE_PER_SEC indicates write bandwidth of specific block like mmcblk0
- DISK_ATTR_READ_TOTAL indicates read kB size of specific block
- DISK_ATTR_WRITE_TOTAL indicates write kB size of specific block

The detailed description[1] of data are from /proc/diskstats and
/sys/class/block/[block name]/stats:
[1] https://www.kernel.org/doc/Documentation/ABI/testing/procfs-diskstats

2. Add skeleton of network resource driver with resource name attribute.
- NETWORK_ATTR_NAME indicates the network device name

Change-Id: Ib440ab628ad1edc5a24378b9c18b80b7c9a8367e
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>