Fixed some typos in the comments of rocksdb options file example

Summary: Fixed some typos in the comments of rocksdb options file example

Test Plan: No code change.

Reviewers: igor, anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D51393

examples/rocksdb_option_file_example.ini

@@ -1,9 +1,10 @@
 # This is a RocksDB option file.
 #
 # A typical RocksDB options file has three sections, which are
-# Version, DBOptions, and more than one CFOptions.  The RocksDB
-# options file in general follows the basic INI file format
-# with the following extensions / modifications:
+# Version section, DBOptions section, at least one CFOptions
+# section, and one TableOptions section for each column family.
+# The RocksDB options file in general follows the basic INI
+# file format with the following extensions / modifications:
 #
 #  * Escaped characters
 #    We escaped the following characters:
@@ -20,7 +21,7 @@
 #    Each statement contains a '=', where extra white-spaces
 #    are supported. However, we don't support multi-lined statement.
 #    Furthermore, each line can only contain at most one statement.
-#  * Section
+#  * Sections
 #    Sections are of the form [SecitonTitle "SectionArgument"],
 #    where section argument is optional.
 #  * List