Permission denied for build.sh file

Looks like you need to check in the file build.sh with execution permissions. Please try the following from your own machine:

git update-index --add --chmod=+x build.sh
git commit -m 'Make build.sh executable'
git push

You can grant the needed permission by adding this lines to the .travis.yml

before_install:
  - chmod +x build.sh

Run the script using bash

Another option would be to run the script using bash, this would omit the need to modify the files' permissions.

bash path/to/file.sh

Alternatively:

sh path/to/file.sh

Note that

In this case you're not executing the script itself, you're executing bash or sh which then runs the script. Therefore the script does not need to be executable.

Make sense?