GfxUtil cannot handle non-pokemon sprites properly

[PsyCommando]

Non-pokemon sprites can contain orphaned images, or images that aren't refered to by any meta-frame. This makes it impossible to determine the size of those images properly.

At the time of writing this, the latest release crashes whenever a sprite with orphaned images is encountered. And the latest code on the master branch handles exporting them to an estimated resolution. But its impossible to properly repack those sprites.

More research into this is needed!

[PsyCommando]

The following sprites aren't parsed correctly:
"d28p34a3.wan"
"d30p33a4.wan"
"d51p11a1.wan"
"d52p32a3.wan"
"d52p32a9.wan"
"d53p41a1.wan"
"d57p43a2.wan"
"h02p99c4.wan"
"h02p99c5.wan"
"p14p01a1.wan"
"s01p01a1.wan"
"s08p01a1.wan"
"s13p01a1.wan"
"s13p03a1.wan"
"s13p03a2.wan"
"s18p01a3.wan"
"s18p01a4.wan"
"s20p01a1.wan"
"s20p01a2.wan"
"v01p05b1.wan"
"v01p05b2.wan"
"v01p05b3.wan"
"v04p03a1.wan"
"v05p03a1.wan"
"v05p03a2.wan"
"v10p03c1.wan"
"v19p06a1.wan"
"v23p04a1.wan"
"v24p04a2.wan"
"v37p02a1.wan"