Enable Opera compatibility

[Frederico Caldeira Knabben]

Introducing the appropriate browser sniffing in the integration files to enable Opera 9.50 compatibility.

Generic rules for the user agent sniffing:

1# Check: Is Opera?

Check if "Opera/" is in UserAgent.

2# Check: Is compatible Opera version?

Get the number (including decimals) after "Opera/". It must be >= 9.50.

[Frederico Caldeira Knabben]

The JavaScript implementation has been introduced with [882].

[Wiktor Walc]

Done with [886],[887],[888],[889],[890],[891],[897].

AFP version has not been tested yet because I couldn't integrate AFP on my computer neither with Apache 2 nor IIS 5.0...

[Frederico Caldeira Knabben]

Sönke, our AFP maintainer, confirmed that the code is correct. He just pointed out that there could be issues with server configured to use commas for decimals separations. He proposed a solution... I've applied it with [907].