ISO 10206 support

Original Reporter info from Mantis: keithbowes

• Reporter name: Keith Bowes

Description:

I'm planning on trying to get Extended Pascal fully supported in FPC, so I'll use this bug to submit incremental patches as I gradually implement it.

Also, semi-on-topic, the Wiki page about Extended Pascal has a couple of errors, so someone with edit permissions should look into it. Namely:
* The mode is called extendedpascal, not extpas (though I wouldn't mind it changing).
* The type access keyword is restricted, not restrictive.

Additional information:

In this first patch, I've implemented the easy things (the 1s on the scale of 1 to 10 like on the Future Plans page). Namely, complex numbers, date/time, and strings.

Mantis conversion info:

• Mantis ID: 32549
• Version: 3.1.1
• Monitored by: » Adriaan van Os (Adriaan van Os), » @KaMiSchi (Karl-Michael Schindler), » @KaiBurghardt (Kai Burghardt)