fix more docs typos

doc/migrating-with-sbr.md

@@ -2,7 +2,7 @@
 
 Even though `gh-ost` relies on Row Based Replication (RBR), it does not mean you can't keep your Statement Based Replication (SBR).
 
-`gh-ost` is happy to, and actually prefers and suggests so, connect to a replica. On this replica, it is happy to:
+`gh-ost` is happy to, and actually prefers and suggests to, connect to a replica. On this replica, it is happy to:
 - issue the heavyweight `INFORMATION_SCHEMA` queries that make a table structure analysis
 - issue a `select count(*) from mydb.mytable`, should `--exact-rowcount` be provided
 - connect itself as a fake replica to get the binary log stream
@@ -11,7 +11,7 @@ All of the above can be executed on the master, but we're more comfortable that
 
 Please note the third item: `gh-ost` connects as a fake replica and pulls the binary logs. This is how `gh-ost` finds the table's changelog: it looks up entries in the binary log.
 
-The magic is that your master can still produce SRB, but if you have a replica with `log-slave-updates`, you can also configure it to have `binlog_format='ROW'`. Such a replica accepts SBR statements from its master, and produces RBR statements onto its binary logs.
+The magic is that your master can still produce SBR, but if you have a replica with `log-slave-updates`, you can also configure it to have `binlog_format='ROW'`. Such a replica accepts SBR statements from its master, and produces RBR statements onto its binary logs.
 
 `gh-ost` is happy to modify the `binlog_format` on the replica for you:
 - If you supply `--switch-to-rbr`, `gh-ost` will convert the binlog format for you, and restart replication to make sure this takes effect.

doc/understanding-output.md

@@ -1,4 +1,4 @@
-# Understading gh-ost output
+# Understanding gh-ost output
 
 `gh-ost` attempts to be verbose to the point where you really know what it's doing, without completely spamming you.
 You can control output levels: