Switch to openssl's vendored feature for musl builds

This should give us updates for free!

.travis.yml

@@ -140,15 +140,7 @@ matrix:
     - rust: nightly
       env: JOB=dist-linux TARGET=x86_64-unknown-linux-musl
       before_script: rustup target add $TARGET
-      install:
-        - travis_retry curl -O https://www.openssl.org/source/openssl-1.0.2o.tar.gz
-        - tar xf openssl-1.0.2o.tar.gz
-        - (cd openssl-1.0.2o &&
-          CC=musl-gcc ./Configure --prefix=$HOME/openssl-musl no-dso no-ssl2 no-ssl3 linux-x86_64 -fPIC &&
-          make -j$(nproc) &&
-          make install)
-        - export OPENSSL_DIR=$HOME/openssl-musl
-      script: cargo build --manifest-path crates/cli/Cargo.toml --release --target $TARGET
+      script: cargo build --manifest-path crates/cli/Cargo.toml --release --target $TARGET --features vendored-openssl
       addons:
         apt:
           packages:

crates/cli/Cargo.toml

@@ -25,3 +25,7 @@ serde_derive = "1.0"
 serde_json = "1.0"
 wasm-bindgen-cli-support = { path = "../cli-support", version = "=0.2.15" }
 wasm-bindgen-shared = { path = "../shared", version = "=0.2.15" }
+openssl = { version = '0.10.11', optional = true }
+
+[features]
+vendored-openssl = ['openssl/vendored']