Make Agavi ready for PHP6

[david]

On the list so far:

• Rename AgaviConfigCache::import() to load()
• Rename AgaviConfig::import() to fromArray(), deprecate AgaviConfig::export() and add toArray() as a replacement
• Add function_exists() calls to all uses of get_magic_quotes_gpc()

[david]

(In [2062]) threw out magic_quotes_runtime (come on...) and unserialize_callback_func ini_set ( http://www.php.net/manual/en/function.unserialize.php#65687), kinda refs #563

[impl]

(In [2064]) BREAKING CHANGES: Make Agavi PHP6-compatible, closes #563 - Rename AgaviConfigCache::import() to load() - Rename AgaviConfig::import() to fromArray() - Deprecate AgaviConfig::export() in favor of toArray()