Fixup mtr_unique. Remove usage of ps and grep. Make it a module. Move _process_alive to Platform.pm. Rename opt_baseport to baseport, it's not an option

manually resolved conflicts:
Text conflict in client/mysqltest.c
Contents conflict in mysql-test/include/have_bug25714.inc
Text conflict in mysql-test/include/have_ndbapi_examples.inc
Text conflict in mysql-test/mysql-test-run.pl
Text conflict in mysql-test/suite/parts/inc/partition_check_drop.inc
Text conflict in mysql-test/suite/parts/inc/partition_layout.inc
Text conflict in mysql-test/suite/parts/inc/partition_layout_check1.inc
Text conflict in mysql-test/suite/parts/inc/partition_layout_check2.inc
Text conflict in mysql-test/suite/parts/r/partition_alter1_1_2_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_alter1_1_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_alter1_2_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_alter2_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_alter3_innodb.result
Text conflict in mysql-test/suite/parts/r/partition_alter3_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_basic_innodb.result
Text conflict in mysql-test/suite/parts/r/partition_basic_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_basic_symlink_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_engine_myisam.result
Text conflict in mysql-test/suite/parts/r/partition_syntax_myisam.result
Text conflict in mysql-test/suite/rpl_ndb/t/disabled.def
Text conflict in mysql-test/t/disabled.def

The problem of this bug is that we need to get the list of tables
to be updated for a multi-table update statement, which requires to
open all the tables referenced by the statement and resolve all
the fields involved in update in order to figure out the list of
tables for update. However if there are replicate filter rules,
some tables might not exist on slave and result in a failure
before we could examine the filter rules.

I think the whole problem can not be solved on slave alone,
the master must record and send the information of tables
involved for update to slave, so that the slave do not need to
open all the tables referenced by the multi-table update statement to
figure out which tables are involved for update.

So a status variable is added to Query_log event to store the
value of table map for update on master. And on slave, it will
try to get the value of this variable and use it to examine
filter rules without opening any tables on slave, if this values
is not available, the old approach is used and thus the bug will
still occur for when replicating from old masters.

test to stall for slave_net_timeout and cause some test case fail

Problem: After START SLAVE, the Slave_IO_Status column of
SHOW SLAVE STATUS goes from No to Yes asynchronously. That
caused sporadic failures on pushbuild in rpl_stm_until since
the test contains SHOW SLAVE STATUS right after START SLAVE.
Fix: Wait until Slave_IO_Status becomes Yes after each
START SLAVE.

Problem: mtr --max-test-fail=0 should allow unlimited number
of errors, but stops after the second error.
Fix: It's just a typo in mysql-test-run.pl