cfg-tree: increase buffer for formatting the location in debug messages

Signed-off-by: Balazs Scheidler <bazsi@balabit.com>
cfg-tree: add log_expr_node_location_tag() function

This new function formats a "location" tag to be emitted as a name-value
pair associated with an internal message. This makes it trivial
to add this information to internal messages.

Signed-off-by: Balazs Scheidler <bazsi@balabit.com>
logpipe: add log_pipe_location_tag() function

This function formats a "location" tag to be emitted as a name-value
pair of internal messages.

Signed-off-by: Balazs Scheidler <bazsi@balabit.com>
global: use log_pipe_location_tag() and log_expr_node_location_tag()

Signed-off-by: Balazs Scheidler <bazsi@balabit.com>
Merge pull request #209 from balabit/f/location-tag-refactor

F/location tag refactor