All Travis CI pull request tests are failing or erroring with the current version of code

[AriAlavi]

If you look at the pull requests, even the smallest changes are causing issues with Travis CI. This indicates that the current build itself is incompatible with the tests.

The following errors are present in almost all pull requests:

Jobs 61.1 / 61.2/ 61.3: ./include/caffe/syncedmem.hpp:81:9: error: unused variable ‘rc’ [-Werror=unused-variable]
Job 61.4 / 61.9: Connecting to developer.download.nvidia.com (developer.download.nvidia.com)|152.195.19.142|:80... connected. HTTP request sent, awaiting response... 404 Not Found 2020-03-03 09:17:55 ERROR 404: Not Found.
Jobs 61.5 / 61.7: No output has been received in the last 10m0s, this potentially indicates a stalled build or something wrong with the build itself. Check the details on how to adjust your build configuration on: https://docs.travis-ci.com/user/common-build-problems/#build-times-out-because-no-output-was-received
Job 61.6: End-of-central-directory signature not found. Either this file is not a zipfile, or it constitutes one disk of a multi-part archive. In the latter case the central directory and zipfile comment will be found on the last disk(s) of this archive. unzip: cannot find zipfile directory in one of gmock-1.7.0.zip or gmock-1.7.0.zip.zip, and cannot find gmock-1.7.0.zip.ZIP, period.
Job 61.8: Multi-node is not supported if CPU_ONLY is disabled. Please set CPU_ONLY=1 if USE_MLSL=1. Call Stack (most recent call first): CMakeLists.txt:70 (include) -- Configuring incomplete, errors occurred!

No job finished successfully.