NUTCH-1825 protocol-http may hang for certain web pages

git-svn-id: https://svn.apache.org/repos/asf/nutch/trunk@1637236 13f79535-47bb-0310-9956-ffa450edef68
NUTCH-1884 NullPointerException in parsechecker and indexchecker with symlinks in file URL

git-svn-id: https://svn.apache.org/repos/asf/nutch/trunk@1637237 13f79535-47bb-0310-9956-ffa450edef68
NUTCH-1887 Specify HTMLMapper to use in TikaParser

git-svn-id: https://svn.apache.org/repos/asf/nutch/trunk@1637325 13f79535-47bb-0310-9956-ffa450edef68