RFR : 8211326 : add OS user related information to hs_err file

[Baesken, Matthias]

Hello , please review this small enhancement to the hs_err file .

Currently the hs_err file contains only limited OS user related information.
Just the user name is printed via output of environment variables (at least on Windows with USERNAME - output).
The enhanced output on UNIX would contain more information including uid, gid and umask  :

uid : 1679 (testuser)
euid : 1679 (testuser)
gid : 25 (testgroup)
egid : 25 (testgroup)

umask: 0022 (removing ----w--w-)


(  Some of the info above could be found currently  in error logging output e.g.
            attachListener_linux.cpp   line 362
            log_debug(attach)("euid/egid check failed (%d/%d vs %d/%d)",
(and the user name on Windows(-only) is in the env variables section).



bug/webrev :
----------------------

https://bugs.openjdk.java.net/browse/JDK-8211326

http://cr.openjdk.java.net/~mbaesken/webrevs/8211326.0/


Thanks, Matthias