Removed empty lines in plugin output
HTML is now valid according to w3 validator (no errors)
Remove typo in the example rrdcached socket documentation
list the different sorts of docs
Merge pull request #107 from dipohl/patch-2

list the different sorts of docs
docs: Add a section about wich sort of documentation to place in Munin's Wiki
docs: Outline sections
docs: Moved one more section from Munin-Wiki page to here (http://munin-monitoring.org/wiki/MuninNomenclature)
docs: more sections to move wiki content to here
docs: rename DocBook to Guide
docs: a further rename
docs: Rename this to "Munin Guide" as we have further documentations areas and need a less general term
docs: Add page about Multigraph Plugins
docs: Add page about Multigraph Protocoll
plugins/df_abs: fix the multiple block device

The special devices like tmpfs or none can appear multiple times,
so we need to append the mount point.

Closes: D#712793
Merge branch 'fix/d/712793' into stable-2.0
plugins: fix typo (Muning::Plugin::HTTP)
Add support for MySQL 5.5/5.6

The mysql plugin named "mysql_" have a problem. So It could not work
fine with MySQL 5.5 or 5.6.
I have make a patch for "INDIVIDUAL BUFFER POOL INFO" section as
skipped to work.

## all of symlinked mysql_ pluugin gets error like below.
```sh
$ /etc/munin/plugins/mysql_connections
Unknown section: INDIVIDUAL BUFFER POOL INFO at
/etc/munin/plugins/mysql_connections line 1098.
```

## related issue
https://github.com/kjellm/munin-mysql/commit/111293966ccd6e8df6c1347cb0f
9a8b4025c0266
mysql_innodb_insert_buf compatibility problem fixed for MySQL 5.5/5.6

The mysql plugin named "mysql_" have a problem. So It could not work
fine with MySQL 5.5 or 5.6.
I have make a patch for "mysql_innodb_insert_buf" to work.

## symlinked from mysql_innodb_insert_buf to mysql_ pluugin gets error
below.
```sh
$ /etc/munin/plugins/mysql_innodb_insert_buf
Use of uninitialized value in printf at
/etc/munin/plugins/mysql_innodb_insert_buf line 885.
ib_ibuf_inserts.value
Use of uninitialized value in printf at
/etc/munin/plugins/mysql_innodb_insert_buf line 885.
ib_ibuf_merged_rec.value
Use of uninitialized value in printf at
/etc/munin/plugins/mysql_innodb_insert_buf line 885.
ib_ibuf_merges.value
```

## related issue
https://github.com/kjellm/munin-mysql/issues/34#issuecomment-1487824
fixed indent