v3.0 - audio / video support

This release closes Issue 108 by providing support for basic use of <audio> and <video> elements.

I say "basic" but it should be more than enough for adding videos and audio files to slides. (python-pptx will actually embed these files in the PowerPoint .pptx - so it's not just a link.)

v2.6.1 TableHeadingSize

New metadata item (both presentation- and slide-level): TableHeadingSize

If non-zero it changes the table heading font size.

Also fixed a bug where a cell spanning more than 2 columns would cause md2pptx to crash. This is why you need at least md2pptx v2.6.1 to use mdpre v0.6.2's =cal / =endcal function.

v2.6 DeleteFirstSlide, Python 3.10, Multi-Column Table Cells

Thanks to Thomas McQuitty for his help with item 112. This adds the ability to delete the first (Processing Summary) slide. Also supporting Python 3.10 (we hope).

Also enhancement item 111 which allows table cells to occupy more than one column. (This behaviour you can turn on and off at the slide and presentation level.)

v2.5.5 Dynamic Margin Specification

marginBase, tableMargin, and numbersHeight control margins around items placed on a slide. You've been able to specify them for the whole presentation. Now you can control them slide-by-slide.

The prime inspiration was a request to remove the margins so e.g. a graphic could occupy the whole slide.

v2.5.4 Content-Type used to detect web graphic types

If a graphic is referenced from the web an attempt is made to use its Content-Type HTTP header. If there is one it will be decoded. Otherwise the file extension will be used (if any).

It's important Content-Type is correctly set - though two common-but-unofficial ones are supported.

The User Guide documents how values for Content-Type are decoded.

Further, a bug where the file extension is incorrectly guessed was fixed - the last dot being before the last dash.

v2.5.3 Exception handlers for temp file creation and URL retrieval

If there is a failure in creation for a temporary file - perhaps because the temporary directory doesn't exist - md2pptx will terminate with a diagnostic (IOError-originated) message.

Similarly for a URL-based graphic retrieval (using information from the HTTPError thrown).

v2.5.2 TempDir Support

You can use the new tempDir metadata item to indicate where md2pptx will store its temporary files. Right now they're only used during graphic conversion or embedding graphics specified using a URL.

v2.5.1 Issue 110 Fixed

Issue 110 fixed.

v2.5 EPS and exportGraphics: yes support

Adds Encapsulated Postscript (EPS) support. Also can exported (inevitably) converted-to-PNG EPS and SVG files to disk.

Also   (non-breaking space) works in text.

Issues addressed: 96, 106, 107

v2.4.3 Indirect Hyperlinks

You can now use indirect hyperlinks - as well as the originally supported reference (inline) hyperlinks.

(Addresses Issue 105.)