Align comments vertically (#290)

This got incorrectly changed as part of normalizing indentation in code
listings to 4 spaces.

Reviewed the changes in 28a4aaf and I
don't see any remaining indentation problems that weren't already fixed
by a130dfc or fixed by this PR.

Author: amartini51

TSPL.docc/LanguageGuide/AccessControl.md

@@ -231,25 +231,25 @@ the default access level of the type's members will be internal.
 > and avoids presenting the internal workings of a type as public API by mistake.
 
 ```swift
-public class SomePublicClass {                  // explicitly public class
+public class SomePublicClass {                   // explicitly public class
     public var somePublicProperty = 0            // explicitly public class member
     var someInternalProperty = 0                 // implicitly internal class member
     fileprivate func someFilePrivateMethod() {}  // explicitly file-private class member
     private func somePrivateMethod() {}          // explicitly private class member
 }
 
-class SomeInternalClass {                       // implicitly internal class
+class SomeInternalClass {                        // implicitly internal class
     var someInternalProperty = 0                 // implicitly internal class member
     fileprivate func someFilePrivateMethod() {}  // explicitly file-private class member
     private func somePrivateMethod() {}          // explicitly private class member
 }
 
-fileprivate class SomeFilePrivateClass {        // explicitly file-private class
+fileprivate class SomeFilePrivateClass {         // explicitly file-private class
     func someFilePrivateMethod() {}              // implicitly file-private class member
     private func somePrivateMethod() {}          // explicitly private class member
 }
 
-private class SomePrivateClass {                // explicitly private class
+private class SomePrivateClass {                 // explicitly private class
     func somePrivateMethod() {}                  // implicitly private class member
 }
 ```

TSPL.docc/ReferenceManual/Attributes.md

@@ -1762,8 +1762,8 @@ into code that calls the static methods of the result builder type:
       func draw() -> String { return content }
   }
   struct Line<D: Drawable>: Drawable {
-        var elements: [D]
-        func draw() -> String {
+      var elements: [D]
+      func draw() -> String {
           return elements.map { $0.draw() }.joined(separator: "")
       }
   }