Adding documentation for PDToPDFgetN

docs/source/algorithms/PDToPDFgetN-v1.rst

+.. algorithm::
+
+.. summary::
+
+.. alias::
+
+.. properties::
+
+Description
+-----------
+
+This is a workflow algorithm that creates files suitable as input
+into `PDFgetN <http://pdfgetn.sourceforge.net/>`_.
+
+#. :ref:`algm-PDLoadCharacterizations`
+#. :ref:`algm-LoadEventAndCompress` if ``InputWorkspace`` is not
+   provided
+#. :ref:`algm-PDDetermineCharacterizations` to determine information
+   from the characterization file
+#. :ref:`algm-AlignAndFocusPowder`
+#. :ref:`algm-NormaliseByCurrent`
+#. :ref:`algm-SetUncertainties` (``SetError="sqrt"``)
+#. :ref:`algm-SaveGSS`
+
+Workflow
+########
+
+.. diagram:: PDToPDFgetN-v1_wkflw.dot
+
+.. categories::
+
+.. sourcelink::

docs/source/diagrams/PDToPDFgetN-v1_wkflw.dot

+digraph AlignAndFocusPowder {
+  label="AlignAndFocusPowder Flowchart"
+  $global_style
+
+  subgraph params {
+    $param_style
+    InputWorkspace
+  }
+
+  subgraph algoritms {
+    $algorithm_style
+    loadChar          [label="PDLoadCharacterizations v1"]
+    loadEvent         [label="LoadEventAndCompress v1"]
+    determineChar     [label="PDDetermineCharacterizations v1"]
+    alignAndFocus     [label="AlignAndFocusPowder v1"]
+    norm              [label="NormaliseByCurrent v1"]
+    setUncert         [label="SetUncertainties v1"]
+    saveGSS           [label="SaveGSS v1"]
+  }
+
+  subgraph decisions {
+    $decision_style
+  }
+
+
+  loadChar         -> determineChar
+  loadEvent        -> InputWorkspace
+  InputWorkspace   -> determineChar
+  InputWorkspace   -> alignAndFocus
+  determineChar    -> alignAndFocus
+  alignAndFocus    -> norm
+  norm             -> setUncert
+  setUncert        -> saveGSS
+}