[ANNOUNCE] NSPR 4.26 Release

[Kai Engert]

The NSPR 4.26 release is now available. The hg tag is
NSPR_4_26_RTM. The source tar file can be downloaded from
https://ftp.mozilla.org/pub/mozilla.org/nspr/releases/v4.26/src/

NSPR 4.26 contains the following changes:
- PR_GetSystemInfo supports a new flag
PR_SI_RELEASE_BUILD to get information about the
operating system build version.
- Better support parallel building on Windows.
- The internal release automatic script requires
python 3.

For details, please refer to the list of related bugs:
https://bugzilla.mozilla.org/buglist.cgi?resolution=FIXED&query_format=advanced&product=NSPR&target_milestone=4.26

Thanks to all contributors to this release.
Kai