Code review comment for lp:~hrvojem/percona-server/bug1056603-5.5

Same comments as in the 5.1 MP plus:

- new docs for INNODB_BUFFER_POOL_PAGES, INNODB_BUFFER_POOL_PAGES_INDEX
  and INNODB_BUFFER_POOL_PAGES_BLOB. I wonder if they deserve a separate
  section, like there are sections for "InnoDB Undo Logs", "Temporary
  Tables", etc.?

- s/These tables show the buffer pool data structure/The following
  tables provide various information about the contents of the InnoDB
  buffer pool/

- s/Possible values,/Possible values:/

- SPACE_ID is the tablespace ID, rather than the table ID

- PAGE_NO is the page offset within its tablespace

- LRU_POSITION is the page position in the LRU list

- FIX_COUNT is the reference count of a page. It is incremented every
  time the page is accessed by InnoDB, and is 0 if and only if the page
  is not currently being accessed

- ACCESS_TIME (in INNODB_BUFFER_POOL_PAGES_INDEX) is not a boolean value
  as the description suggests. It is the time of the last access to that
  page.