Improve search logging
Improve search logging

Rexi receives an error message that does not match any of the tuples
for the first argument of dreyfus_fabric:handle_error_message/6. This
leads to a function_clause error that bubbles up to chttpd which gets
logged because there is a stack trace involved. By adding an extra
clause that matches all error messages, we attempt to see if progress
can be made by calling handle_error. If progress can succeed, then
nothing gets logged. If the progress cannot succeed, an error will be
sent back to the user again via chttpd:send_error/2. However, if no
stack trace is involved in the error, we won't log the message. Adding
an extra couch_log:error here assures we have something in the logs to
make note of the error message to help us debug.

BugzId: 75421

cloudant-labs/dreyfus