makeRests now makes rests that can be exported to MusicXML (non-complex duration)

[gregchapman-dev]

No description provided.

[gregchapman-dev]

This is the third split-out PR from PR #1768

[coveralls]

coverage: 93.002% (+0.004%) from 92.998%
when pulling 1784fb7 on gregchapman-dev:gregc/makeRestsShouldSplitThem
into eb5a88f on cuthbertLab:master.

[mscuthbert]

Closing PR -- non issue. Works as intended:

    def test_msc(self):
        r = note.Rest(5.0)
        r.style.hideObjectOnPrint = True
        n = note.Note()
        s = stream.Measure([r, n])
        print(self.getXml(s))

    <measure implicit="no" number="0">
      <attributes>
        <divisions>10080</divisions>
        <time>
          <beats>6</beats>
          <beat-type>4</beat-type>
        </time>
        <clef>
          <sign>G</sign>
          <line>2</line>
        </clef>
      </attributes>
      <note print-object="no" print-spacing="yes">
        <rest />
        <duration>40320</duration>
        <type>whole</type>
      </note>
      <note print-object="no" print-spacing="yes">
        <rest />
        <duration>10080</duration>
        <type>quarter</type>
      </note>
      <note>
        <pitch>
          <step>C</step>
          <octave>4</octave>
        </pitch>
        <duration>10080</duration>
        <type>quarter</type>
      </note>
    </measure>

The code given here deliberately disables the checks to make sure that notation is coherent and then asserts a bug that the system fails on incoherent notation.

No further PRs with makeNotation=False will be reviewed.