 docs(sqlite): Add interface for transaction callback function argument (#2586)
 docs(sqlite): Add interface for transaction callback function argument (#2586)

The transaction callback function argument is currently typed as `any`, however this isn't very  helpful so I have added a base interface which contains only the `executeSql` function. This function is all that is available on the object returned by WebSQL, but is also available on the full SQLite implementation.
driftyco/ionic-native,driftyco/ionic-native,driftyco/ionic-native