Add alpine (musl) prebuild

Author: vweevers

.travis.yml

@@ -32,6 +32,11 @@ jobs:
       node_js: node
       env: [BUILD_CMD=prebuild-arm, BUILD_GROUP=arm, NPM_CONFIG_IGNORE_SCRIPTS=1]
       if: tag is present
+    - name: alpine
+      os: linux
+      node_js: node
+      env: [BUILD_CMD=prebuild-alpine, BUILD_GROUP=alpine, NPM_CONFIG_IGNORE_SCRIPTS=1]
+      if: tag is present
 
 script:
   - if [[ ! -z "$TEST" ]]; then npm run test; fi

package.json

@@ -21,7 +21,8 @@
     "prebuild-linux-armv7": "IMAGE=linux-armv7 ./scripts/cross-compile --tag-armv",
     "prebuild-linux-arm64": "IMAGE=linux-arm64 ./scripts/cross-compile --tag-armv",
     "prebuild-android-armv7": "IMAGE=android-armv7 ./scripts/cross-compile --tag-armv",
-    "prebuild-android-arm64": "IMAGE=android-arm64 ./scripts/cross-compile --tag-armv"
+    "prebuild-android-arm64": "IMAGE=android-arm64 ./scripts/cross-compile --tag-armv",
+    "prebuild-alpine": "IMAGE=alpine ./scripts/cross-compile --tag-libc"
   },
   "dependencies": {
     "abstract-leveldown": "~6.0.3",