Boltforms doesn't see database tables not starting with "bolt_"

I've been playing with the `database` option to store submission data to a separate table, because I don't want to create a contenttype for that, so I manually created a table named `boltforms_contact_us`, but it came to my attention that the mechanism Boltform uses to query tables ignores tables created manually and always throws an error `missing database table 'boltforms_contact_us'`, even though it's definitely there and contains all appropriate columns. To check my assumption, I dumped `$tables`, and indeed the list didn't contain manually created tables and only listed those created by Bolt. As I lack PHP knowledge, I've no idea how to fix this myself and I had to remove the part of code that checks if the table exists. As soon as I did this, the form data successfully started to save to my custom table. So I'll have to leave it like that for now, but I really do hope that this issue will be fixed in future versions.

Start by reproducing the issue with a manually created `boltforms_contact_us` table and inspect the table-discovery check that rejects it. Done means Boltforms recognizes manually created tables and saves form submissions without removing the existence check.

Written by the indexing model from the issue text.