Fixed BSONTest.testUTF8 to ignore surrogate characters, which are not valid UTF-8 characters, so that the test passes on Java 8.
Fixed BSONTest.testUTF8 to ignore surrogate characters, which are not valid UTF-8 characters, so that the test passes on Java 8.

jyemin/mongo-java-driver,gianpaj/mongo-java-driver,jyemin/mongo-java-driver,jsonking/mongo-java-driver,kay-kim/mongo-java-driver,PSCGroup/mongo-java-driver,rozza/mongo-java-driver,jsonking/mongo-java-driver,rozza/mongo-java-driver