Reraise the caught bottle exception

The commit 6df119b5b1 introduced an handler to catch all REST API
exceptions to sanitize them before log them. But it raises the backtrace of
the exception with HTTP error 500 instead of reraise the caught bottle
HTTP error to the client.

Change-Id: If5a9184b59e66c741cd5675f2bcf74fe67ad0769
Merge "Reraise the caught bottle exception"