Description

This PR removes support for MySQL 5.5.x, which reached end-of-life on December 3, 2018

For the most part this PR removes testing for 5.5.x and a single hack to support 5.5.x in go/logic/inspect.go. This hack assumed binlog_row_image=FULL if the query for this global-variable failed, as it will do on 5.5.x (variable doesn't exist)

Removing this hack should make things more resilient in a situation where the select @@global.binlog_row_image query fails for a different reason

In case this PR introduced Go code changes:

• contributed code is using same conventions as original code
• script/cibuild returns with no formatting errors, build errors or unit test errors.