Update file structure inside `Dial-Up Infrastructure' documentation
    manual. The manual structure looks like the following:
    
    Preface
        1. Overview
        2. Document Convenctions
        3. Send In Your Feedback
    I. The Server Computer
        1. Dial-Up Server Usage
            1.1. Overview
            1.2. Administering Dial-Up Connections
            1.3. Administering Users Accounts
            1.4. Administering Internet Services
            1.5. Administering Disk Space
        2. Dial-Up Server Installation
            2.1. Overview
            2.2. Installing Server Hardware
            2.3. Installing Server Software
        3. Dial-Up Server Configuration
            3.1. Overview
            3.2. Configuring Server Hardware
            3.3. Configuring Server Software
    II. The Client Computer
        4. Dial-Up Client Usage
        5. Dial-Up Client Installation
            5.1. Overview
            5.2. Installing Client Hardware
            5.3. Installing Client Software
        6. Dial-Up Client Configuration
            6.1. Overview
            6.2. Configuring Client Hardware
            6.3. Configuring Client Software
    III. Licenses
        A. GNU Free Documentation License
            A.1. Preamble
            A.2. Applicability and definitions
            A.3. Verbatim copying
            A.4. Copying in quantity
            A.5. Modifications
            A.6. Combining documents
            A.7. Collection of documents
            A.8. Aggregation with independent works
            A.9. Translations
            A.10. Termination
            A.11. Future Revisions of this License
            A.12. How to use this License for your documents