Beautify and reword a bit.

Zend/README.ZEND_MM

@@ -1,13 +1,34 @@
-The goal of the new memory manager (PHP 5.2 and later) is reducing memory allocation overhead and speedup memory management.
+Zend Memory Manager
+===================
 
-The new manager's "configure" has no "--disable-zend-memory-manager" option, but it has "--enable-malloc-mm" instead. It is enabled by default in DEBUG build and disabled by default in RELEASE built. It allows select malloc/emalloc at runtime.  So you can use internal and external memory debuggers without recompilation.
+General:
+--------
 
-$ sapi/cli/php -r 'leak();'
+The goal of the new memory manager (available since PHP 5.2) is to reduce memory
+allocation overhead and speedup memory management.
 
-$ USE_ZEND_ALLOC=0 valgrind --leak-check=full -r 'leak();'
+The new manager's "configure" has no "--disable-zend-memory-manager" option,
+but it has "--enable-malloc-mm" instead.  It is enabled by default in DEBUG
+build and disabled by default in RELEASE build.  when enabled it allows selecting
+between malloc and emalloc at runtime so you can use internal and external memory
+debuggers without recompilation.
 
-The patch allows tweaking memory manager with ZEND_MM_MEM_TYPE and ZEND_MM_SEG_SIZE environment variables. Default values are "malloc" and "256K". Dependent on target system you can also use "mmap_anon", "mmap_zero"
-and "win32" storage managers.
+Debugging:
+----------
 
-$ ZEND_MM_MEM_TYPE=mmap_anon ZEND_MM_SEG_SIZE=1M sapi/cli/php
+Normal:
 
+    $ sapi/cli/php -r 'leak();'
+
+Zend MM disabled:
+
+    $ USE_ZEND_ALLOC=0 valgrind --leak-check=full sapi/cli/php -r 'leak();'
+
+Tweaking:
+---------
+
+The Zend MM can be tweaked using ZEND_MM_MEM_TYPE and ZEND_MM_SEG_SIZE environment
+variables.  Default values are "malloc" and "256K". Dependent on target system you
+can also use "mmap_anon", "mmap_zero" and "win32" storage managers.
+
+	$ ZEND_MM_MEM_TYPE=mmap_anon ZEND_MM_SEG_SIZE=1M sapi/cli/php ..etc.