p/cpu: add 10% tolerance to field.max to avoid loosing data
node: adding some __FILE__ debug directives
plugins: reorder source files to ease future diffs

We put main.c at the end of the list to each plugin can be added
alphabetically, without always changing the last backlash hanling
Merge branch 'fixes'

Conflicts:
	src/plugins/Makefile.am
plugins: adding an external_ wildcard plugin