Images will be loaded from an external source (e.g. http://example.com/img.png) only if the reader is explicitly set to allow it via `$reader->setAllowExternalImages(true)`.
* All Readers - Allow or Forbid Fetching of External Images Release390
Add to all readers the option to allow or forbid fetching external images. This is unconditionally allowed now. The default will be set to "allow", so no code changes are necessary. However, we are giving consideration to changing the default.
* Update Changelog
For the second time in recent months, some tests are failing/erring because https file_get_contents is not working on github (cannot reproduce locally on Windows or Linux). Filed an issue with Php when this first happened, and their suggested code change worked till now. If they come up with another successful code change, I will implement it and restore these tests.
oleibman
