Update contributor text

Author: ibmmqmet

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,6 +1,6 @@
 Please ensure all items are complete before opening.
 
-- [ ] Tick to sign-off your agreement to the [IBM Contributor License Agreement](https://github.com/ibm-messaging/mq-golang/CLA.md)
+- [ ] Tick to sign-off your agreement to the [Developer's Certificate of Origin](https://github.com/ibm-messaging/mq-golang/DCO1.1.txt)
 - [ ] You have added tests for any code changes
 - [ ] You have updated the [CHANGES.md](https://github.com/ibm-messaging/mq-golang/CHANGES.md)
 - [ ] You have completed the PR template below:

CLA.md

@@ -0,0 +1,25 @@
+Developer's Certificate of Origin 1.1
+
+       By making a contribution to this project, I certify that:
+
+       (a) The contribution was created in whole or in part by me and I
+           have the right to submit it under the open source license
+           indicated in the file; or
+
+       (b) The contribution is based upon previous work that, to the best
+           of my knowledge, is covered under an appropriate open source
+           license and I have the right under that license to submit that
+           work with modifications, whether created in whole or in part
+           by me, under the same open source license (unless I am
+           permitted to submit under a different license), as indicated
+           in the file; or
+
+       (c) The contribution was provided directly to me by some other
+           person who certified (a), (b) or (c) and I have not modified
+           it.
+
+       (d) I understand and agree that this project and the contribution
+           are public and that a record of the contribution (including all
+           personal information I submit with it, including my sign-off) is
+           maintained indefinitely and may be redistributed consistent with
+           this project or the open source license(s) involved.

DCO1.1.txt

@@ -206,10 +206,11 @@ or extended are welcomed.
 For feedback and issues relating specifically to this package, please use
 the [GitHub issue tracker](https://github.com/ibm-messaging/mq-golang/issues).
 
-Contributions to this package can be accepted under the terms of the IBM Contributor
-License Agreement, found in the [CLA file](CLA.md) of this repository. When
+Contributions to this package can be accepted under the terms of the Developer's Certificate
+of Origin, found in the [DCO file](DCO1.1.txt) of this repository. When
 submitting a pull request, you must include a statement stating you accept the terms
-in the CLA.
+in the DCO.
+
 
 ## Copyright