add back .cargo/config for flags only, remove cross-env dep

.cargo/config

@@ -0,0 +1,2 @@
+[build]
+rustflags = ["-C", "link-args=-s"]

.travis.yml

@@ -4,5 +4,5 @@ rust:
 before_install:
   - rustup target add wasm32-unknown-unknown
 script:
-  - npm install && npm run build
+  - npm run build
   - cargo test --package status-message -- --nocapture

package.json

@@ -3,7 +3,7 @@
   "version": "1.0.0",
   "description": "Compiles NEAR Protocol example of setting and retrieving a status message per NEAR account",
   "scripts": {
-    "build": "cross-env RUSTFLAGS=\"-C link-arg=-s\" cargo build --target wasm32-unknown-unknown --release",
+    "build": "cargo build --target wasm32-unknown-unknown --release",
     "postbuild": "cp target/wasm32-unknown-unknown/release/status_message.wasm ./res/"
   },
   "repository": {
@@ -22,7 +22,5 @@
     "url": "https://github.com/near-examples/rust-status-message/issues"
   },
   "homepage": "https://github.com/near-examples/rust-status-message#readme",
-  "devDependencies": {
-    "cross-env": "^7.0.2"
-  }
+  "devDependencies": {}
 }