Use panic=abort instead of panic=unwind

jrmuizel · jrmuizel · commit 6af8c836e1da · 2017-10-06T13:49:54.000-04:00
This is the same mode as Gecko uses and will get better codegen once rust-lang/rust#45012 has landed.
diff --git a/Cargo.toml b/Cargo.toml
@@ -7,3 +7,4 @@ members = [
 
 [profile.release]
 debug = true
+panic = "abort"
