update coding.md to reflect changes by pull

- also mention alphabetical include ordering

doc/coding.md

@@ -4,7 +4,7 @@ Coding
 Please be consistent with the existing coding style.
 
 Block style:
-
+```c++
     bool Function(char* psz, int n)
     {
         // Comment summarising what this section of code does
@@ -19,12 +19,33 @@ Block style:
         // Success return is usually at the end
         return true;
     }
-
+```
 - ANSI/Allman block style
 - 4 space indenting, no tabs
 - No extra spaces inside parenthesis; please don't do ( this )
 - No space after function names, one space after if, for and while
+- Includes need to be ordered alphabetically, separate own and foreign headers with a new-line (example key.cpp):
+```c++
+#include "key.h"
+
+#include "crypto/sha2.h"
+#include "util.h"
+
+#include <openssl/foo.h>
+```
+- Class or struct keywords in header files need to be ordered alphabetically:
+```c++
+class CAlpha;
+class CBeta;
+```
+- When using namespace keyword use the following form:
+```c++
+namespace Foo {
 
+...
+
+} // Foo
+```
 Variable names begin with the type in lowercase, like nSomeVariable.
 Please don't put the first word of the variable name in lowercase like
 someVariable.