made the pack completely portable and wrote relevent bat files to go with it

gitportable/mingw64/share/doc/git-doc/git-write-tree.adoc

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+git-write-tree(1)
+=================
+
+NAME
+----
+git-write-tree - Create a tree object from the current index
+
+
+SYNOPSIS
+--------
+[verse]
+'git write-tree' [--missing-ok] [--prefix=<prefix>/]
+
+DESCRIPTION
+-----------
+Creates a tree object using the current index. The name of the new
+tree object is printed to standard output.
+
+The index must be in a fully merged state.
+
+Conceptually, 'git write-tree' sync()s the current index contents
+into a set of tree files.
+In order to have that match what is actually in your directory right
+now, you need to have done a 'git update-index' phase before you did the
+'git write-tree'.
+
+
+OPTIONS
+-------
+--missing-ok::
+	Normally 'git write-tree' ensures that the objects referenced by the
+	directory exist in the object database.  This option disables this
+	check.
+
+--prefix=<prefix>/::
+	Writes a tree object that represents a subdirectory
+	`<prefix>`.  This can be used to write the tree object
+	for a subproject that is in the named subdirectory.
+
+GIT
+---
+Part of the linkgit:git[1] suite