Remove the buggy and complex awk(1) magic in "plugins-scripts/subst.in"
in favor of simple sed(1) substitutions.
The plugins in the "plugins-scripts" directory now always use the PATH
specified via "./configure --trusted-path", or the default PATH
hard-coded in "configure.ac".
Fixes#1242.
When configuring the plugins you have the option to specify a trusted path with --with-trusted-path. This option seems to have been deprecated at some point for unknown reasons and had typically had no affect. This commit makes this option work again for those who have a desire to use it. There should be no affect on those who have not chosen to specify a trusted path.
Return an UNKNOWN status if a faulty sensor is detected. This can be
suppressed with the new "--ignore-fault" option.
(Fixes Debian bug #615133, patch suggested by Jan Wagner.)
