feat(build): restore build scope and add osx os

Restore the Travis build scope for Go versions after testing.

Add OSX as an OS build target.

Fixes #225

.travis.yml

@@ -4,14 +4,15 @@ sudo: false
 language: go
 
 go:
-  #- "1.8.x"
-  #- "1.9.x"
-  #- "1.10.x"
+  - "1.8.x"
+  - "1.9.x"
+  - "1.10.x"
   - "1.11.x"
-  #- tip
+  - tip
 
 os:
   - linux
+  - osx
   - windows
 
 matrix:
@@ -20,6 +21,7 @@ matrix:
   - go: tip
 
 install:
+  - if [[ "$TRAVIS_OS_NAME" == "windows" ]]; then git config --global core.autocrlf true ; fi
   - make install-devtools
   - make deps