Improve cache size calculation of PCode objects in general.

Also trick the RAM cache manager to set a low cost on entries coming
from persistent storage.
Pike 8.0: Fixed some compilation errors in tasks.

Fixes some of [bug 7362].
Pike 8.0: Stdio.get_all_active_fd() is no longer an efun too.

Fixes compilation errors for the "Open files" task.

Fixes remainder of [bug 7362].
Tasks/SSL: No need to keep compat with broken Netscape from 2000.

It's been 14 years since the Netscape browser that didn't like
UTF-8 strings in certificates was common...
Merge branch 'patches/pike8.0' into devel

* patches/pike8.0:
  Tasks/SSL: No need to keep compat with broken Netscape from 2000.
  Pike 8.0: Stdio.get_all_active_fd() is no longer an efun too.
  Pike 8.0: Fixed some compilation errors in tasks.