Validate parameter inputs against regex prior to S3 upload

[andrew-glenn]

It'd be nice to validate parameter inputs against the AllowedPattern prior to uploading to S3.

[andrew-glenn]

maybe during param generation.. after generation, reconcile the output against the allowed regex.

[andrew-glenn]

@jaymccon @avattathil - thoughts?

[jaymccon]

Aside from failing faster are there any other benefits ?

[andrew-glenn]

Just failing faster, but it also means there's no resource creation if the params don't match the allowedpattern regex.

[jaymccon]

with the new config handling the get_rendered_parameters method depends on having buckets already created. In the absence of a more compelling reason to remove this dependency I think we should close this.