Renamed all mhl files as some of them are also present under /usr/include

with the same name:
 - memory.h
 - string.h
In order to do not have two .h files with the same name these two needs to be renamed.
I've renamed the others too, in order to have the same naming rules here.

Updated README to reflect this change

mhl/README

@@ -10,7 +10,7 @@ This is a tiny library of helper functions/macros.
 
 --
 
-memory.h:	Memory management functions
+mhlmemory.h:	Memory management functions
 
     * mhl_mem_alloc_u(sz)				[MACRO-FUNC]
     
@@ -34,7 +34,7 @@ memory.h:	Memory management functions
 	like mhl_mem_free(), but with ptr as a variable that gets cleared
 	(use this as shortcut to "mhl_mem_free(foo); foo = NULL")
 
-string.h:	String helpers
+mhlstring.h:	String helpers
 
     * mhl_str_dup(const char*s) -> char*
 
@@ -75,7 +75,7 @@ string.h:	String helpers
 	[INLINE-FUNC] Reverses the string in passed buffer and returns the buffer ptr itself.
 	If NULL is passed, returns NULL.
 
-shell_escape.h:	Shell-style string escaping
+mhlescape.h:	Shell-style string escaping
 
     * mhl_shell_escape_toesc(char c) 	-> bool
 
@@ -95,7 +95,7 @@ shell_escape.h:	Shell-style string escaping
 	[INLINE-FUNC] unescapes the string into given buffer (changes buffer!) and 
 	returns ptr to the buffer itself. When NULL passed returns NULL.
 
-env.h:	Environment variable helpers
+mhlenv.h:	Environment variable helpers
 
     * mhl_getenv_dup(const char* n)	-> char*
     

mhl/mhlstrhash.h

@@ -2,7 +2,7 @@
 #define __MHL_STRHASH_H
 
 #include <hash.h>
-#include "../mhl/memory.h"
+#include "../mhl/mhlmemory.h"
 
 static void __mhl_strhash_free_key(void* ptr)
 {

mhl/mhlstring.h

@@ -3,7 +3,7 @@
 
 #include <ctype.h>
 #include <stdarg.h>
-#include "../mhl/memory.h"
+#include "../mhl/mhlmemory.h"
 
 #define	mhl_str_dup(str)	((str ? strdup(str) : strdup("")))
 #define mhl_str_ndup(str,len)	((str ? strndup(str,len) : strdup("")))