AddingPowerSupport_CI/Testing (#234)

* Update .travis.yml

Adding Power & Updating the go versions to 1.13/1.14/1.15 as lower versions are not supported.

* Update .travis.yml

Removing go 1.13 as desired in the comment section,

* Update .travis.yml

As desired taking out the power(ppc64le) related support.,
diff --git a/.travis.yml b/.travis.yml
index 9159de0..81e650b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,11 @@
+arch:
+  - amd64
+  
 language: go
 go_import_path: github.com/pkg/errors
 go:
-  - 1.11.x
-  - 1.12.x
-  - 1.13.x
+  - 1.14
+  - 1.15
   - tip
 
 script: