[clang-format] Fix document of AlignTrailingComments

[yusuke-kadowaki]

Summary

The documentation of the patch https://reviews.llvm.org/D132131 looks disorganized on the website https://clang.llvm.org/docs/ClangFormatStyleOptions.html.
This patch tries to fix that.

[yusuke-kadowaki]

Add a blankline after the endcode to deal with the Buildbot error.
https://lab.llvm.org/buildbot/#/builders/92/builds/34906

[yusuke-kadowaki]

Thank you.
Please land when you have time.

name: Yusuke Kadowaki
email: [e-mail]

clang/docs/ClangFormatStyleOptions.rst

AlignTrailingComments:
       Kind: Always
       OverEmptyLines: 2
 
   Nested configuration flags:
 
   Alignment options
 
   * ``TrailingCommentsAlignmentKinds Kind``
-    Specifies the way to align trailing comments
+    Specifies the way to align trailing comments.
 
     Possible values:
 
     * ``TCAS_Leave`` (in configuration: ``Leave``)
       Leave trailing comments as they are.
 
       .. code-block:: c++
 
* ``TCAS_Never`` (in configuration: ``Never``)
 
         int a; // comment
         int ab; // comment
 
         int abc; // comment
         int abcd; // comment
 
 
-  * ``unsigned OverEmptyLines`` How many empty lines to apply alignment
-    With ``MaxEmptyLinesToKeep`` is 2 and ``OverEmptyLines`` is 2,
+  * ``unsigned OverEmptyLines`` How many empty lines to apply alignment.
+    When both ``MaxEmptyLinesToKeep`` and ``OverEmptyLines`` are set to 2,
+    it formats like below.
 
     .. code-block:: c++
 
       int a;      // all these
 
       int ab;     // comments are
 
 
       int abcdef; // aligned
 
-    And with ``MaxEmptyLinesToKeep`` is 2 and ``OverEmptyLines`` is 1,
+    When ``MaxEmptyLinesToKeep`` is set to 2 and ``OverEmptyLines`` is set
+    to 1, it formats like below.
 
     .. code-block:: c++
 
       int a;  // these are
 
       int ab; // aligned
 
 

clang/include/clang/Format/Format.h

enum TrailingCommentsAlignmentKinds : int8_t {
     ///   int abc; // comment
     ///   int abcd; // comment
     /// \endcode
     TCAS_Never,
   };
 
   /// Alignment options
   struct TrailingCommentsAlignmentStyle {
-    /// Specifies the way to align trailing comments
+    /// Specifies the way to align trailing comments.
     TrailingCommentsAlignmentKinds Kind;
-    /// How many empty lines to apply alignment
-    /// With ``MaxEmptyLinesToKeep`` is 2 and ``OverEmptyLines`` is 2,
+    /// How many empty lines to apply alignment.
+    /// When both ``MaxEmptyLinesToKeep`` and ``OverEmptyLines`` are set to 2,
+    /// it formats like below.
     /// \code
     ///   int a;      // all these
     ///
     ///   int ab;     // comments are
     ///
     ///
     ///   int abcdef; // aligned
     /// \endcode
-    /// And with ``MaxEmptyLinesToKeep`` is 2 and ``OverEmptyLines`` is 1,
+    ///
+    /// When ``MaxEmptyLinesToKeep`` is set to 2 and ``OverEmptyLines`` is set
+    /// to 1, it formats like below.
     /// \code
     ///   int a;  // these are
     ///
     ///   int ab; // aligned
     ///
     ///
     ///   int abcdef; // but this isn't
     /// \endcode