contrib/script: error text corrections in check_updates.sh

Fix a factual error in the /contrib/check_updates.sh error message text,
Best shown in an example from the latest travis build error:
```
$ ./contrib/check_updates.sh auth auth
Database Updater check script:
  Checking database 'auth' for missing filenames in tables...

- "sql/updates/2015_10_09_00_auth.sql" is missing in table 'auth'.'updates'

Fatal error:
  The Database Updater is broken for database 'auth
  due to applied update which are missing in the 'auth'.'updates' table.

How to fix:
  Insert the missing names of sql updates which were applied already to
  the 'updates' table of the 'auth' base dump ('sql/base/auth_database.sql').

The command "./contrib/check_updates.sh auth auth" exited with 1.
```
Main fix: `\"sql/updates/${file}\"` -> `\"sql/updates/${name}/${file}\"`

Before this change, the error message claims that the updated SQL file was placed
directly in the `/sql/updates/` directory and not in the subdirectory based on its DB name.

All the other changes are improvements in English grammar and more precise description.

0 files changed, 0 insertions, 0 deletions