Renamed $field['message'] = $field['error']
Update file class
Added new file admin features & small bug fixes
Update URL class
Update main class

Updates:
- new request starting time.
- incorporated URL class updates.
Update file class
Rename domain -> host
Incorporated File class in the core
Moved generic classes, core -> util

Affected:
- File
- Session
- URL
URL class, enable method chaining

Features:
- method chaining
- set directory
- set file
Incorporated new URL class features