Date_ToDebugString

Add a function `Date_ToDebugString` that allows the user to see the raw content of an `s_date` type

Fix round trip conversion on date objects:
```c
	s_date date = Date_FromString("22 April 1937 UTC", "%d %B %Y %Z");
        printf(C_CYAN"DATE %s"C_RESET"\n", Date_ToString(&date, "%d %B %Y %Z"));
```
returns 
```
DATE 22 April 1937 CET
```