HBASE-19023 Replace hbase-server with hbase-mapreduce for HBase and MapReduce chapter
RowCounter and other related HBase's MapReduce classes have been moved
to hbase-mapreduce component by HBASE-18640, related chapter was
out-of-date and this fix replaced hbase-server with hbase-mapreduce
to correct those commands
Also this change moved RowCounter_Counters.properties to
hbase-mapreduce package as well
JIRA https://issues.apache.org/jira/browse/HBASE-19023
Signed-off-by: tedyu <yuzhihong@gmail.com>