update: add static build to CI.

Signed-off-by: Kim Kulling <[email protected]>

.travis.yml

@@ -4,6 +4,8 @@ before_install:
 env:
   - TRAVIS_NO_EXPORT=YES
   - TRAVIS_NO_EXPORT=NO
+  - TRAVIS_STATIC_BUILD=ON
+  - TRAVIS_STATIC_BUILD=OFF
 
 language: cpp
 
@@ -11,7 +13,7 @@ compiler:
   - gcc
   - clang
 
-script: cmake -G "Unix Makefiles" -DASSIMP_ENABLE_BOOST_WORKAROUND=YES -DASSIMP_NO_EXPORT=$TRAVIS_NO_EXPORT && make
+script: cmake -G "Unix Makefiles" -DASSIMP_ENABLE_BOOST_WORKAROUND=YES -DASSIMP_NO_EXPORT=$TRAVIS_NO_EXPORT -STATIC_BUILD=$TRAVIS_STATIC_BUILD && make