Disable incremental on CI for now

It seems... buggy!

.appveyor.yml

@@ -2,6 +2,7 @@ environment:
   global:
     RUSTFLAGS: -Zunstable-options -Ctarget-feature=+crt-static
     RUST_BACKTRACE: 1
+    CARGO_INCREMENTAL: 0   # should turn this back on when fixed!
   matrix:
     - TARGET: x86_64-pc-windows-msvc
       DEPLOY: 1

.travis.yml

@@ -1,6 +1,10 @@
 language: rust
 sudo: false
 
+env:
+  global:
+    - CARGO_INCREMENTAL=0
+
 matrix:
   include:
     # CLI builds on stable