Update .travis.yml and coverage script

.travis.yml

@@ -16,7 +16,7 @@ install:
  - go get -v ./...
 
 script:
- - go test -v -coverprofile=coverage.txt -covermode=atomic ./...
+ - ./coverage.sh
 
 after_success:
  - bash <(curl -s https://codecov.io/bash)

coverage.sh

@@ -0,0 +1,23 @@
+#!/bin/sh
+
+set -e
+
+workdir=.cover
+profile=${workdir}/cover.out
+mode=count
+
+generate_cover_data() {
+    rm -rf ${workdir}
+    mkdir ${workdir}
+
+    for pkg in "$@"; do
+        f="${workdir}/$(echo ${pkg} | tr / -).cover"
+        go test -covermode=${mode} -coverprofile=${f} ${pkg}
+    done
+
+    echo "mode: ${mode} > ${profile}"
+    grep -h -v "^mode:" "${workdir}"/*.cover >>"${profile}"
+}
+
+generate_cover_data $(go list ./...)
+mv ${profile} coverage.txt