Updated Texassemble (markdown)

Texassemble.md

@@ -18,6 +18,7 @@ texassemble <command>
     [-fl feature-level]
     [-bgcolor]
     [-swizzle rgbamask]
+    [-stripmips]
     <file-name(s)>
 ```
 
@@ -87,6 +88,8 @@ The file-name parameter indicates the file(s) to use to create the assembled ima
 
 > The ``merge`` command default swizzle mask matches the legacy DirectX Texture Tool behavior when doing "Open Alpha onto Surface..."
 
+**-stripmips**: For the ``cube``, ``array``, ``volume``, or ``cubearray`` command, the input images are expected to be single images. This option allows mip-mapped 1D or 2D textures to be used as inputs, which removes the mip-chain during processing.
+
 # Examples
 
 ```