[Enhancement] Allow for replacement of token values in the scripts @ runtime

[GoogleCodeExporter]

This is a feature idea (And I am sorry if this can be achieved another way 
which I have yet to find), but essentially, our requirements is that we want to 
let the user installing the DB enter in a new / existing credentials that will 
be used to run our application under.

What I am thinking is that we could have our permissions scripts modified 
before sending the script to the DB so that the script could be updated with 
the correct values. 

So for example if you have 

CREATE LOGIN '%%LOGIN%%'

And we pass a parameter (Could be cmd line, or set as an environment variable 
or any other method). That RH would replace the %%LOGIN%% with the value we 
want.

Original issue reported on code.google.com by [email protected] on 13 Sep 2010 at 6:17