Create pull_request_template.md requiring the license approval

[evandrocoan]

All new pull-requests, before being merged, should already have approved the open-source license being discussed on:

1. Created the LICENSE as represented on the github issue #1175 #1570 - Created the LICENSE as represented on the github issue Can it be an open source project? #1175

To approve the open-source license, hit the review now button at the sidebar, as shown in the following image, and type I agree with this license for my code. as the pull-request view message:

1. 
2.