logging: Support for Structured logging format

Wrapper for `gf_log` and `gf_msg` to add support for
structured logging format.

Two new wrappers available `gf_slog` and `gf_smsg`

Example 1: All static details

    gf_slog ("cli", GF_LOG_INFO, "Volume Set",
             "name=gv1",
             "option=changelog.changelog",
             "value=on",
             NULL);

    gf_smsg ("cli", GF_LOG_INFO, 0, MSGID_VOLUME_SET,
             "Volume Set",
             "name=gv1",
             "option=changelog.changelog",
             "value=on",
             NULL);

Example 2: Using Format chars in key values

    gf_slog ("cli", GF_LOG_INFO, "Volume Set",
             "name=%s", volume_name,
             "option=%s", option_name,
             "value=%s", option_value,
             NULL);

    gf_smsg ("cli", GF_LOG_INFO, 0, MSGID_VOLUME_SET,
             "Volume Set",
             "name=%s", volume_name,
             "option=%s", option_name,
             "value=%s", option_value,
             NULL);

Formats as,

    <EVENT><TAB><KEY1=VALUE1><TAB><KEY2=VALUE2>...

Example:

    Volume Set	name=gv1	option=changelog.changelog	value=on

Updates: #240
Change-Id: I871727be16a39f681d41f363daa0029b8066fb52
Signed-off-by: Aravinda VK <avishwan@redhat.com>
Reviewed-on: https://review.gluster.org/17543
Reviewed-by: MOHIT AGRAWAL <moagrawa@redhat.com>
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Tested-by: Amar Tumballi <amarts@redhat.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>

0 files changed, 0 insertions, 0 deletions