INNODB_COMPRESSION_BUDDY and INNODB_COMPRESSION_BUDDY_RESET.

buf_buddy_stat_struct, buf_buddy_stat_t, buf_buddy_stat[]:
Statistics of the buddy system grouped by block size.

i_s_innodb_compression_buddy, i_s_innodb_compression_buddy_reset:
New INFORMATION_SCHEMA plugins.

i_s_compression_buddy_fields_info[]: Define the fields:
size, used, free, relocated, relocated_sec.

i_s_compression_buddy_fill_low(), i_s_compression_buddy_fill(),
i_s_compression_buddy_reset_fill(): Fill the fields.

i_s_compression_buddy_init(), i_s_compression_buddy_reset_init():
Initialize the tables.