Convert instance indices to UUIDs in configuration
Convert instance indices to UUIDs in configuration

cfgupgrade replaces the occurences of instance names (where they are
used as index) with the instance UUID.

It also supports the inverse replacement, so downgrades are
supported too.

Signed-off-by: Thomas Thrainer <98bdeac947eb8ca18146e9ce7f092788ec242cd1@google.com>
Reviewed-by: Klaus Aehlig <4ce51de36d9068cd7db2eec1151e0f3f95419008@google.com>

dimara/ganeti,apyrgio/ganeti,ganeti-github-testing/ganeti-test-1,grnet/snf-ganeti,leshchevds/ganeti,leshchevds/ganeti,bitemyapp/ganeti,mbakke/ganeti,leshchevds/ganeti,bitemyapp/ganeti,apyrgio/ganeti,dimara/ganeti,apyrgio/snf-ganeti,yiannist/ganeti,ganeti/ganeti,apyrgio/snf-ganeti,andir/ganeti,mbakke/ganeti,onponomarev/ganeti,ganeti-github-testing/ganeti-test-1,andir/ganeti,mbakke/ganeti,yiannist/ganeti,ganeti/ganeti,grnet/snf-ganeti,onponomarev/ganeti,yiannist/ganeti,andir/ganeti,ganeti/ganeti