Implement various missing features for the ODT writer

[oleibman]

Implement a number of features implemented in PhpWord,
but not yet supported in PhpWord ODT Writer.

1. Add default file to tests/PhpWord/_includes/XmlDocument.php to make it
   considerably easier to test ODT changes (and Word2007 changes involving
   files other that document.xml).
2. Page break before each section.
3. Page numbering start.
4. Font style for Headings.
5. Alignment for images.
6. Paragraph style for TextRun.
7. "Hide grammatical errors" for whole document.
8. Page layout for each section.
9. For each page layout, support user-specified page width, page height,
   orientation, margin top, margin bottom, margin left, margin right.
10. Page header and footer.
11. Named colors.
12. NoProof font style.
13. Paragraph Style - spaceBefore, spaceAfter, lineHeight, pageBreakBefore,
    indentation, text alignment.
14. Tab stops.
15. Basic support for some Fields (DATE, PAGE, NUMPAGES).
16. Link had an error in how it was handling internal links (needs leading #).
17. In addition to tests for all the above, added some tests for Tables.

Item 11 above needs 1 module from Pull Request 1775, which is targeted
for v0.18.0 but not yet merged, so the relevant module is also here.
Item 15 above needs 1 module from Pull Request 1774, which is targeted
for v0.18.0 but not yet merged, so the relevant module is also here.
Testing change from Pull Request 1771 is included here, but was
merged after my fork.

Description

Please include a summary of the change and which issue is fixed. Please also include relevant motivation and context.

Fixes # (issue)

Checklist:

• I have run composer run-script check --timeout=0 and no errors were reported
• The new code is covered by unit tests (check build/coverage for coverage report)
• I have updated the documentation to describe the changes

[coveralls]

Coverage increased (+0.3%) to 94.904% when pulling 4e347b3 on oleibman:odtchanges into 733f845 on PHPOffice:develop.

[oleibman]

I am completely baffled by the remaining Scrutinizer issue. In Writer\ODText\Element\Title,
I have the following code at line 43:
if ($elems[0] === $element) {
$hdname = 'HE';
}
Scrutinizer reports that the test condition is always false. However, this is the only place where I set
the header name to HE*, and I have a number of tests which assert that HE* is the style name in use,
and these tests all pass, so it's clear, at least to me, that the test condition is not always false.
These tests are:
tests/PhpWord/Writer/ODText/ElementTest.php line 152 (in testTitleAndHeading)
tests/PhpWord/Writer/ODText/Styles/ParagraphTest.php lines 288, 304, 313, and 336
(in testHeadingPageBreakBefore).
I also added an echo in there in a test version, and confirmed that it is reaching the code in
question, by the way.
So, any advice on what needs to be done here?

Two lesser Scrutinizer items that I may as well mention now.

Writer/ODText/Style/Paragraph needs to test whether Indentation is null or not before using it.
Scrutinizer said it was always an instance, but it can be null.
But Style/Paragraph had not said this was a possibility, so I changed the docblock to allow this. Nevertheless, Scrutinizer still complained.
I changed my test from (instanceof Indentation) to (empty), and now Scrutinizer was happy.

Scrutinizer reported a problem in Writer\ODText\Element\TextRun on the following code:
$element = $this->getElement();
$pStyle = $element->getParagraphStyle();
The error was that getParagraphStyle doesn't exist on PhpOffice\PhpWord\Element\AbstractElement.
But it does exist on PhpOffice\PhpWord\Element\TextRun. It said I could eliminate the error
with an annotation, which I did, but I'm not proud of it. I'm just not sure what a better
method of correcting the problem would be. Incidentally, the same code is in
Writer\ODText\Element\Text.