pySim-shell: Add suspend_uicc command

This is an optional command, and it is not supported by e.g.  sysmoISIM-SJA2

Change-Id: Icc726ffd672744e56cc8dd3762891af507942c1e
diff --git a/docs/shell.rst b/docs/shell.rst
index 5bc86ae..3d56c6d 100644
--- a/docs/shell.rst
+++ b/docs/shell.rst
@@ -156,6 +156,20 @@
    :func: Iso7816Commands.close_chan_parser
 
 
+suspend_uicc
+~~~~~~~~~~~~
+This command allows you to perform the SUSPEND UICC command on the card.  This is a relatively
+recent power-saving addition to the UICC specifications, allowing for suspend/resume while maintaining
+state, as opposed to a full power-off (deactivate) and power-on (activate) of the card.
+
+The pySim command just sends that SUSPEND UICC command and doesn't perform the full related sequence
+including the electrical power down.
+
+.. argparse::
+   :module: pySim-shell
+   :func: Iso7816Commands.suspend_uicc_parser
+
+
 pySim commands
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