Sybase/MSSQL: Fix for repeated EED messages
. Fix repeated EED messages leading to "Unknown token" messages
. Enhance test to actually fail on master branch
. Empty messages before logging in and before issuing queries
. No longer empty messages on every read
. QA: Add apidoc link to Sybase TDS v5 spec
. Merge all messages into the exception cause
See xp-framework/xp-framework#360