Initial commit which adds: retries when request fails, config-ed timeouts per service, and error logging, to fix #223.  Also removes unused code in home() to fix #227.
Added AQUABROWSER_RETRIES (forgot to add with last commit)
Added more detail to log message
Added logging formatter configuration
Reduced default timeout settings for summon and aquabrowser to 2 x 5 sec; also reduced libsite timeout to 5 sec
simplified error logging
Resolved merge conflicts
Removed extraneous merge marking
Merge pull request #228 from gwu-libraries/t223-error-handling

T223 error handling