Updated to Xcode 8.3 on Travis, and added legacy Mac build, targeting…

… older OS version (Issue #47)

.travis.yml

@@ -1,7 +1,7 @@
 language:
   - objective-c
 
-osx_image: xcode8.2
+osx_image: xcode8.3
 
 before_install:
     # Used to allow pushing to CocoaPods only after all matrixed builds have succeeded
@@ -19,6 +19,11 @@ matrix:
     - script: xcodebuild -workspace UnzipKit.xcworkspace -scheme UnzipKit -sdk macosx -configuration Release analyze test -skip-testing:UnzipKitTests/ExtractFilesTests/testExtractZip64_LargeFile -skip-testing:UnzipKitTests/ExtractFilesTests/testExtractZip64_ManyFiles ENABLE_NS_ASSERTIONS=1 CLANG_ANALYZER_OUTPUT=html CLANG_ANALYZER_OUTPUT_DIR=analyzer-output && [[ -z `find analyzer-output -name "*.html"` ]]
       env: Name=Mac
 
+      # The CLANG arguments and find command fail the build on analyzer errors
+    - script: xcodebuild -workspace UnzipKit.xcworkspace -scheme UnzipKit -sdk macosx -configuration Release analyze test -skip-testing:UnzipKitTests/ExtractFilesTests/testExtractZip64_LargeFile -skip-testing:UnzipKitTests/ExtractFilesTests/testExtractZip64_ManyFiles ENABLE_NS_ASSERTIONS=1 CLANG_ANALYZER_OUTPUT=html CLANG_ANALYZER_OUTPUT_DIR=analyzer-output && [[ -z `find analyzer-output -name "*.html"` ]]
+      env: Name=Mac (Legacy)
+      osx_image: xcode6.4
+
       # The CLANG arguments and find command fail the build on analyzer errors
     - script: xcodebuild -workspace UnzipKit.xcworkspace -scheme UnzipKit-iOS -destination 'platform=iOS Simulator,name=iPhone 7,OS=latest' -configuration Release analyze test ENABLE_NS_ASSERTIONS=1 CLANG_ANALYZER_OUTPUT=html CLANG_ANALYZER_OUTPUT_DIR=analyzer-output && [[ -z `find analyzer-output -name "*.html"` ]]
       env: Name=iOS