Delay instance tagging to later in the instance creation process

Tagging recently created instances can result in
InvalidInstanceID.NotFound errors.

By delaying the tagging until the last part of instance creation,
we should be typically more fortunate (avoiding all such race
conditions might need more work)
Handle integer param values that are calculated values

Fixes #7828
return properties of the newly created scaling policy
In check mode if a symlink does not exist there is no need to check the ownership properties (which causes an exception)
Merge branch 'issue_7828_rds_param_group' into devel
Merge pull request #7827 from willthames/delay_tagging_in_ec2

ec2 module: Delay instance tagging to later in the instance creation process
Merge pull request #7829 from bennojoy/asg_policy

return properties of the newly created scaling policy
Merge pull request #7836 from trbs/file_symlink_notexists_checkmode

OSError in file module for non existing symlink in check mode.