ImageMagick distfile churn

["John D. Baker" <jdbaker%mylinuxisp.com@localhost>]

"graphics/ImageMagick" was recently updated to v7.0.8.0.  When my
'pkg_rolling-replace' got around to building it a few days later, the
distfile for ImageMagick-7.0.8-0.tar.* was not available from any master
or mirror site.

Looking on on "ftp.imagemagick.org" shows that upstream have moved on
to ImageMagick-7.0.8-1.* and the previous "-0" distfile has been removed.

I haven't looked to see if they haven't moved on from that yet, but the
latest such distfile should be stashed somewhere less volatile and the
package updated accordingly.

Likely an important issue as the freeze for and eventual branch of
pkgsrc-2018Q2 approaches.

Thanks.

-- 
|/"\ John D. Baker, KN5UKS               NetBSD     Darwin/MacOS X
|\ / jdbaker[snail]mylinuxisp[flyspeck]com    OpenBSD            FreeBSD
| X  No HTML/proprietary data in email.   BSD just sits there and works!
|/ \ GPGkeyID:  D703 4A7E 479F 63F8 D3F4  BD99 9572 8F23 E4AD 1645