Improvement to Easylist.txt import

[kaplun]

There's a series of entries in https://easylist.to/easylist/easylist.txt with the format:

||html-load.com^$popup
||htmonster.com^$popup
||htoptracker11072023.com^$popup
||hue2b.com^$popup
||hue2n.com^$popup
||hue4c.com^$popup
||hueads.com^$popup
||hugeedate.com^$popup
||hugregregy.pro^$popup

or

||89263907.xyz^$document,popup
||89407765.xyz^$document,popup
||91301246.xyz^$document,popup
||92790388.xyz^$document,popup
||94597672.xyz^$document,popup
||98140548.xyz^$document,popup
||98738797.xyz^$document,popup
||98853171.xyz^$document,popup
||content-loader.com^$document,popup
||css-load.com^$document,popup
||ea6c0ac4.xyz^$document,popup
||html-load.cc^$document,popup
||html-load.com^$document,popup
||img-load.com^$document,popup

These are perfectly valid self-contained domains that could be included into the export. It is sufficient to strip the trailint $document,popup or $popup suffixes.