reduce image width for responsive design

account/eth_address_book_in_thunderbird.markdown

...e_userparameters_binary_blob_in_active_directory.markdown

backups/backuppc_osx.markdown

calendar/groupware.markdown

calendar/outlook.markdown

mail/how_to_use_email_with_apple_mail.markdown

mail/how_to_use_email_with_outlook_on_mac.markdown

mail/how_to_use_email_with_thunderbird.markdown

network/how_to_get_network_access.markdown

osx/802_1x.markdown

osx/apple_tv.markdown

osx/filevault.markdown

osx/print_settings.markdown

osx/unicodeit.markdown

osx/vpn_mac.markdown

printing/authenticate_id_printer.markdown

services/lvmchart.markdown

web/how_to_add_our_certificate_to_firefox.markdown

...ws/how_to_change_file_associations_in_windows_xp.markdown

windows/self_managed_windows_machines.markdown