Column name sanity checks on cartodbfy

[danicarrion]

Typical case:

create table books (Id integer, Name text);

Now, if you cartodbfy the table, it'll show up on the editor. However, the editor will fail to work properly with the table, because it'll fail to double-quote "Id" and "Name" on the SQL queries it sends, for instance, to filter data or to change the style of the map.

That's because our editor doesn't deal with column names that need to be put inside double quotes. We could tackle that, or we could let our users know that they need to do the sanity check themselves, but maybe a good trade off between complexity and bad UX could be to make cdb_cartodbfytable perform the sanity checks (and possibly correct what's wrong) itself.

cc @cartodave