Adds subspec workaround. (#23)

* Adds subspec workaround.

Example/Podfile

@@ -1,4 +1,6 @@
+## Without use_frameworks!
 target 'Segment-Firebase_Example' do
+  # Use default subspec
   pod 'Segment-Firebase', :path => '../'
   
   target 'Segment-Firebase_Tests' do
@@ -9,3 +11,23 @@ target 'Segment-Firebase_Example' do
     pod 'Expecta'
   end
 end
+
+
+## With use_frameworks!
+# Use only 'Segment-Firebase/StaticLibWorkaround'
+
+#use_frameworks!
+#
+#target 'Segment-Firebase_Example' do
+#    pod 'Segment-Firebase/StaticLibWorkaround', :path => '../'
+#    pod 'Firebase'
+#
+#end
+#
+#target 'Segment-Firebase_Tests' do
+#    inherit! :search_paths
+#
+#    pod 'Specta'
+#    pod 'Expecta'
+#    pod 'OCMockito'
+#end

Makefile

@@ -1,5 +1,5 @@
 SDK ?= "iphonesimulator"
-DESTINATION ?= "platform=iOS Simulator,name=iPhone 5"
+DESTINATION ?= "platform=iOS Simulator,name=iPhone 7"
 PROJECT := Segment-Firebase
 XC_ARGS := -scheme $(PROJECT)-Example -workspace Example/$(PROJECT).xcworkspace -sdk $(SDK) -destination $(DESTINATION) ONLY_ACTIVE_ARCH=NO
 

Segment-Firebase.podspec

@@ -33,4 +33,14 @@ Pod::Spec.new do |s|
     # This will bundle in Firebase Dynamic Link support
     dynamiclinks.dependency 'Firebase/DynamicLinks', '~> 4.0'
   end
+
+
+  s.subspec 'StaticLibWorkaround' do |workaround|
+    # For users who are unable to bundle static libraries as dependencies
+    # you can choose this subspec, but be sure to include the folling in your podfile
+    # pod 'Firebase'
+    # Please manually add the following file preserved by Cocoapods to your xcodeproj file
+    workaround.preserve_paths = 'Segment-Firebase/Classes/**/*'
+  end
+
 end