Table layout when using empty cells and custom tags

[raducoravu]

I have this Markdown table:

| 11 | 22 | 33 | 44 |
|---|---|---|---|
| A1 || B1 | C1 |
| A2 | B2 | C2 | D2<type>E2 |
| A3 | B3 | C3 | D3 |

Rendered in GitHub it looks like this:

11	22	33	44
A1		B1	C1
A2	B2	C2	D2E2
A3	B3	C3	D3

Converted to a DITA topic it looks like this:

            <table>
                <tgroup cols="4">
                    <colspec colname="col1"/>
                    <colspec colname="col2"/>
                    <colspec colname="col3"/>
                    <colspec colname="col4"/>
                    <thead>
                        <row>
                            <entry>11</entry>
                            <entry>22</entry>
                            <entry>33</entry>
                            <entry>44</entry>
                        </row>
                    </thead>
                    <tbody>
                        <row>
                            <entry namest="col1" nameend="col2">A1</entry>
                            <entry>B1</entry>
                            <entry>C1</entry>
                        </row>
                        <row>
                            <entry>A2</entry>
                            <entry>B2</entry>
                            <entry>C2</entry>
                            <entry>D2<type>E2</type></entry>
                            <row>
                                <entry>A3</entry>
                                <entry>B3</entry>
                                <entry>C3</entry>
                                <entry>D3</entry>
                            </row>
                        </row>
                    </tbody>
                </tgroup>
            </table>

So what we notice in the converted DITA table:

1. The cell "A1" spans over two columns when converted to DITA XML with this project. When rendered in GitHub, the cell does not span two columns.
2. The fact there is that unescaped <type> content there breaks completely the layout of the last row which becomes engulfed inside the next to last row.