If one user in a set of users for validation is an illegal user name, the entire call fails

[MrCreosote]

Instead allow skipping invalid user names in the same way non-existent user names are skipped.

auth2/src/us/kbase/auth2/service/api/Users.java

Lines 64 to 73 in a9939a9

	for (final String u: usersplt) {
	try {
	uns.add(new UserName(u.trim()));
	} catch (MissingParameterException | IllegalParameterException e) {
	//TODO CODE this exception could use some clean up
	throw new IllegalParameterException(ErrorType.ILLEGAL_USER_NAME, String.format(
	"Illegal user name [%s]: %s", u, e.getMessage()));
	}
	}
	return uns;