Travis CI: fix coverity branch build and improve formatting

Also try to cache /usr/local/Cellar for OS X builds.

.travis.yml

@@ -13,6 +13,7 @@ cache:
   timeout: 500
   directories:
   - $HOME/Library/Caches/Homebrew
+  - /usr/local/Cellar
 
 matrix:
   exclude:
@@ -64,13 +65,23 @@ before_install:
 before_script:
 - mkdir build
 - cd build
-- test $TRAVIS_BRANCH != coverity_scan || exit 0
-- source $TRAVIS_BUILD_DIR/CI/get_package_name.sh
-- cmake -G "Unix Makefiles" .. $VCMI_CMAKE_FLAGS -DPACKAGE_NAME_SUFFIX:STRING="$VCMI_PACKAGE_NAME_SUFFIX" -DPACKAGE_FILE_NAME:STRING="$VCMI_PACKAGE_FILE_NAME"
-
+- if [[ $TRAVIS_BRANCH != 'coverity_scan' ]];
+  then
+    source $TRAVIS_BUILD_DIR/CI/get_package_name.sh;
+    cmake -G "Unix Makefiles" .. $VCMI_CMAKE_FLAGS
+      -DPACKAGE_NAME_SUFFIX:STRING="$VCMI_PACKAGE_NAME_SUFFIX"
+      -DPACKAGE_FILE_NAME:STRING="$VCMI_PACKAGE_FILE_NAME";
+  fi
+  
 script:
 - test $TRAVIS_BRANCH != coverity_scan || exit 0
-- if [[ $TRAVIS_OS_NAME == 'osx' ]]; then cd ..; xcodebuild -project osx/osx-vcmibuilder/vcmibuilder.xcodeproj/ -configuration Release CONFIGURATION_BUILD_DIR=..; cd build; fi
+- if [[ $TRAVIS_OS_NAME == 'osx' ]];
+  then
+    cd ..;
+    xcodebuild -project osx/osx-vcmibuilder/vcmibuilder.xcodeproj/
+      -configuration Release CONFIGURATION_BUILD_DIR=..;
+    cd build;
+  fi
 - make -j2
 
 after_success: