m1/tools/README: m1nor description

m1/tools/README

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+m1nor - Flash a file to M1 NOR partition selected by the file name
+==================================================================
+
+During software development, one often need to update only the
+content of a single partition. reflash_m1.sh is a bit unwieldy
+for this kind of task.
+
+I've written a small script called m1nor that selects the target 
+partition based on the file name. E.g., m1nor flickernoise.fbi
+would update the regular Flickernoise partition.
+
+The matching algorithm checks the beginning of the file name,
+so names like flickernoise-test.fbi would also work. Furthermore,
+it checks the file extension, so if you try to flash flickernoise
+(ELF, for debugging) or flickernoise.bin (an intermediate form
+unsuitable for booting from NOR), it will politely refuse to do
+so.
+
+You need to have fjmem.bit somwehere. It searches for it under
+$HOME/.qi/milkymist/, where reflash_m1.sh caches it. You can also
+specify the location directly by setting the environment variable
+FJMEM_BIT.