crypt32: Add a root store implementation that reads trusted certificates from well-known locations on the local system.

crypt32: Add a function to create a certificate chain engine potentially before the root store is created.

ntdll: Remove the overly-cautious check which prevented NtSetSystemTime from changing the time by more than two minutes.

Simplify the returning of different status codes by not playing around 
with the return value from settimeofday.