travis: add custom apt sources

Move back to Travis's VM infrastructure for efficiency.

(cherry picked from commit 9dc21efd)

.travis.yml

@@ -2,7 +2,6 @@
 # see travis-ci.org for details
 
 language: c
-dist: trusty
 
 os:
   - linux
@@ -21,25 +20,25 @@ env:
   - OPTIONS="-DTHREADSAFE=ON -DCMAKE_BUILD_TYPE=Release"
   - OPTIONS="-DTHREADSAFE=OFF -DBUILD_EXAMPLES=ON"
 
-addons:
-  apt:
-    sources:
-     - sourceline: 'deb https://dl.bintray.com/libgit2/ci-dependencies trusty libgit2deps'
-       key_url: 'https://bintray.com/user/downloadSubjectPublicKey?username=bintray'
-    packages:
-    - cmake
-    - curl
-    - libcurl3
-    - libcurl3-gnutls
-    - libcurl4-gnutls-dev
-    - libssh2-1-dev
-    - openssh-client
-    - openssh-server
-    - valgrind
-
 dist: trusty
-sudo: true
 osx_image: xcode8.3
+sudo: false
+
+addons:
+ apt:
+  sources:
+   - sourceline: 'deb http://libgit2deps.edwardthomson.com trusty libgit2deps'
+     key_url: 'https://pgp.mit.edu/pks/lookup?op=get&search=0x5656187599131CD5'
+  packages:
+   cmake
+   curl
+   libcurl3
+   libcurl3-gnutls
+   libcurl4-gnutls-dev
+   libssh2-1-dev
+   openssh-client
+   openssh-server
+   valgrind
 
 matrix:
  fast_finish: true
@@ -65,7 +64,7 @@ matrix:
    - env: COVERITY=1
 
 install:
-  - ./script/install-deps-${TRAVIS_OS_NAME}.sh
+  - if [ -f ./script/install-deps-${TRAVIS_OS_NAME}.sh ]; then ./script/install-deps-${TRAVIS_OS_NAME}.sh; fi
 
 # Run the Build script and tests
 script:

script/install-deps-linux.sh

-#!/bin/sh
-
-set -x
-
-if [ -z "$PRECISE" ]; then
-    echo "deb http://libgit2deps.edwardthomson.com trusty libgit2deps" | sudo tee -a /etc/apt/sources.list
-    sudo apt-key adv --keyserver pgp.mit.edu --recv 99131CD5
-    sudo apt-get update -qq
-    sudo apt-get install -y curl libcurl3 libcurl3-gnutls libcurl4-gnutls-dev
-fi
-
-sudo apt-get install -y cmake libssh2-1-dev openssh-client openssh-server valgrind