Better RAM Usage, proper null safety

Null safety added to some FS functions

Don't attempt to open multiple 15 MB files at once

Some strings changes so the themeplaza browser is better

source/fs.c

@@ -210,6 +210,11 @@ u32 file_to_buf(FS_Path path, FS_Archive archive, char ** buf)
     if(size != 0)
     {
         *buf = calloc(1, size);
+        if (*buf == NULL)
+        {
+            DEBUG("Error allocating buffer - out of memory??\n");
+            return 0;
+        }
         FSFILE_Read(file, NULL, 0, *buf, size);
     }
     FSFILE_Close(file);
@@ -474,8 +479,13 @@ void remake_file(FS_Path path, FS_Archive archive, u32 size)
     }
     FSUSER_CreateFile(archive, path, 0, size);
     char * buf = calloc(size, 1);
-    buf_to_file(size, path, archive, buf);
-    free(buf);
+    if (buf == NULL)
+    {
+        DEBUG("out of memory - not overwriting file?\n");
+    } else {
+        buf_to_file(size, path, archive, buf);
+        free(buf);
+    }
 }
 
 static SwkbdCallbackResult fat32filter(void * user, const char ** ppMessage, const char * text, size_t textlen)