Provide a way to disable VersionCheck in XB 2.1.6
|Percona XtraBackup||Status tracked in 2.2|
Since VersionCheck will be enabled by default in XB 2.1.6, there must be a way to disable it. However, the --version-check option is not 'negatable' (in GetOpt::Long terms), i.e. there is no way to use the same option to disable it when it is enabled by default.
It should be made negatable, so that it's possible to disable VersionCheck with "innobackupex --no-version-