plugins: fix typo (Muning::Plugin::HTTP)
master/limits: global default for always_send

On "nagios" and "old-nagios" contact, there is a default for the "always_send"
directive : "critical warning".

This commit makes it the default for *every* contact.
Remove use of removed Munin::{Master,Node}::Logger
use "eq" when comparing with undef
Merge remote branch 'pull/202' into devel

Conflicts:
	plugins/node.d/apache_volume.in
Merge pull request #206 from steveschnepp/fix-always_send

master/limits: global default for always_send
p/diskstats: enable warn levels in conf

Now we can configure the warning levels on disk latency directly via the node
configuration file.

Note that we reuse the previous value as a default.
Merge remote branch 'pull/208' into devel
Merge branch 'devel' into json
logging: add explicit names to use old version
log: info is default to stdout
json: return the first json with nodes