fix: base64 images not rendered inside of html

[compojoom]

I'm not sure when this happened, but default base64 encoded images were no longer rendered in html text.

If the image is rendered like this:

<img src="data:image/png;base64,....." />

the image was not rendered when inside of an html text. Instead one has to replace data:image/png;base64, with @which in my opinion is not ideal and an overhead.

#179

[CLAassistant]

All committers have signed the CLA.

[nicolaasuni]

Please try to resolve the conflicts.

[compojoom]

@williamdes I rebased. Sorry for the changelog change, but it seems you had an empty space and my IDE wants to remove it :)

[williamdes]

@williamdes I rebased. Sorry for the changelog change, but it seems you had an empty space and my IDE wants to remove it :)

That's okay

But can you remove the other commits?
git reset hard on the base and cherry pick 605d0a1 then force push?

[compojoom]

how about now?

[williamdes]

perfect

[nicolaasuni]

Unfortunately the proposed change has security implications as the file_exist function is used in other places too.
This may allow an attacker to provide arbitrary executable content somewhere.
A proper solution will require a bit of thinking but I'd rather put the energy to complete tc-lib-pdf that already has 90+% of the TCPDF features.