Removed outdated and needless CSS rules

Removed flex-direction default value row
Removed FF19 stable outdated property -moz-box-pack
Removed needless wrapper-nav and Ajax timeout

Suppress mysql_num_rows() errors
Removed needless wrapper-nav
Removed Ajax timeout; default timeout is 0 undefined what means it
totally dependent on browser and network settings
Improved MySQL table and specifications, new example "Nested URL"

Improved MySQL
- global server timezone to GMT
- table specifications
- added rows `updated` and `created`
- create trigger `updated` to handle last modified NOW()
- added data for Nested URL example
Added MySQL trigger `updated`

Added last modified NOW() handler with MySQL trigger `updated`
Improved MySQL select with latest specifications, @@global.time_zone

Handled MySQL @@global.time_zone for accurate header cache