[Server][DBClientHatohol] Change table names and constant value names.

Table Names:
    groups ->
hostgroups
    hosts_groups ->
map_hosts_hostgroups

Constant Value Names:
TABLE_NAME_GROUPS ->
TABLE_NAME_HOSTGROUPS
TABLE_NAME_HOSTSGROUPS ->
TABLE_NAME_MAP_HOSTS_HOSTGROUPS
[Server][DBClientHatohol] Change constant value names.

COLUMN_DEF_GROUPS ->
COLUMN_DEF_HOSTGROUPS

NUM_COLUMNS_GROUPS ->
NUM_COLUMNS_HOSTGROUPS

IDX_GROUPS_* ->
IDX_HOSTGROUPS_*

NUM_IDX_GROUPS ->
NUM_IDX_HOSTGROUPS
[Server][DBClientHatohol] Change constant value names.

COLUMN_DEF_HOSTSGROUPS          ->
COLUMN_DEF_MAP_HOSTS_HOSTGROUPS

NUM_COLUMNS_HOSTSGROUPS           ->
NUM_COLUMNS_MAP_HOSTS_HOSTSGROUPS

IDX_HOSTSGROUPS_*          ->
IDX_MAP_HOSTS_HOSTGROUPS_*

NUM_IDX_MAP_HOSTSGROUPS      ->
NUM_IDX_MAP_HOSTS_HOSTGROUPS