Catch Internal Errors

Catch internal errors and log error message:

Excon::Errors::InternalServerError

/Users/bweaver/.rvm/gems/ruby-1.9.3-p385@simple_deploy_example/gems/excon-0.20.0/lib/excon/middlewares/expects.rb:10:in `response_call': Expected(200)
<=> Actual(500 InternalServerError) (Excon::Errors::InternalServerError)
request => {:chunk_size=>1048576, :connect_timeout=>60, :headers=>{"Content-Type"=>"application/x-www-form-urlencoded; charset=utf-8", "Host"=>"sdb.u
s-west-1.amazonaws.com:443", "Content-Length"=>215}, :idempotent=>true, :instrumentor_name=>"excon", :middlewares=>[Excon::Middleware::Expects, Excon::
Middleware::Idempotent, Excon::Middleware::Instrumentor, Excon::Middleware::Mock], :mock=>false, :nonblock=>true, :read_timeout=>60, :retry_limit=>4, :
ssl_ca_file=>"/Users/bweaver/.rvm/gems/ruby-1.9.3-p385@simple_deploy_example/gems/excon-0.20.0/data/cacert.pem", :ssl_verify_peer=>true, :uri_parser=>U
RI, :write_timeout=>60, :host=>"sdb.us-west-1.amazonaws.com", :path=>"/", :port=>"443", :query=>nil, :scheme=>"https", :user=>nil, :password=>nil, :fam
ily=>0, :body=>"AWSAccessKeyId=XXX&Action=ListDomains&SignatureMethod=HmacSHA256&SignatureVersion=2&Timestamp=2013-03-12T17%3A24%3A05Z
&Version=2009-04-15&Signature=XXXX", :expects=>200, :method=>"POST", :response_block=>#, :retries_remaining=>1}
response => #"\nInternalErrorRe
quest could not be executed due to an internal service errorXXX", :headers=>{"Transfer-Encoding"=>"chunked", "Date"=>"Tue, 12 Mar 2013 17:24:05 GMT", "Cneonction"=>"close", "Server"=>"Amazon SimpleDB"}, :stat
us=>500, :remote_ip=>"XXX"}, @body="\nInternalErrorRequest could not
be executed due to an internal service errorXXX", @header
s={"Transfer-Encoding"=>"chunked", "Date"=>"Tue, 12 Mar 2013 17:24:05 GMT", "Cneonction"=>"close", "Server"=>"Amazon SimpleDB"}, @status=500, @remote_i
p="XXX">