Added first cut of Coverity Scan support

.travis.yml

@@ -1,3 +1,9 @@
+env:
+  global:
+   # The next declaration is the encrypted COVERITY_SCAN_TOKEN, created
+   #   via the "travis encrypt" command using the project repo's public key
+   - secure: "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"
+
 matrix:
   fast_finish: true
   include:
@@ -32,5 +38,30 @@ script:
    - mkdir build
    - cd build
    - travis_wait 60 cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../product -DBUILD_OSG_EXAMPLES=ON ..
-   - make install -j3
+   - make install -j 4
 
+addons:
+  coverity_scan:
+
+    # GitHub project metadata
+    # ** specific to your project **
+    project:
+      name: "openscenegraph/osg"
+      description: "OpenSceneGraph"
+      version: 3.5
+
+    # Where email notification of build analysis results will be sent
+    notification_email: robert@openscenegraph.com
+
+    # Commands to prepare for build_command
+    # ** likely specific to your build **
+    build_command_prepend: cmake -DOSG_USE_AGGRESSIVE_WARNINGS=0 .
+
+    # The command that will be added as an argument to "cov-build" to compile your project for analysis,
+    # ** likely specific to your build **
+    build_command: make -j 4
+
+    # Pattern to match selecting branches that will run analysis. We recommend leaving this set to 'coverity_scan'.
+    # Take care in resource usage, and consider the build frequency allowances per
+    #   https://scan.coverity.com/faq#frequency
+    branch_pattern: coverity_scan