Add new checkboxes for Xcode plugin

This change allows for the user to specify the following checkboxes:
* Upload Bitcode?
* Upload Symbols?
* Compile Bitcode?

The plugin defaults to these checkboxes being checked, so I kept those
defaults here.

Change-Id: I727611fd2a70f2157b05d030ec296c74a5b214a8

tests/builders/fixtures/xcode.xml

@@ -30,6 +30,9 @@
       <keychainPath/>
       <keychainPwd/>
       <unlockKeychain>false</unlockKeychain>
+      <compileBitcode>true</compileBitcode>
+      <uploadBitcode>true</uploadBitcode>
+      <uploadSymbols>true</uploadSymbols>
       <manualSigning>false</manualSigning>
     </au.com.rayh.XCodeBuilder>
     <au.com.rayh.DeveloperProfileLoader>
@@ -64,6 +67,9 @@
       <keychainPath>/Users/jenkins/Library/Keychains/jenkins-uasdk-ios-pre_review</keychainPath>
       <keychainPwd>testpass</keychainPwd>
       <unlockKeychain>true</unlockKeychain>
+      <compileBitcode>false</compileBitcode>
+      <uploadBitcode>false</uploadBitcode>
+      <uploadSymbols>false</uploadSymbols>
       <manualSigning>true</manualSigning>
       <provisioningProfiles>
         <au.com.rayh.ProvisioningProfile>

tests/builders/fixtures/xcode.yaml

@@ -18,6 +18,9 @@ builders:
       ipa-export-method: ad-hoc
       ipa-version: "${VERSION}"
       ipa-output: "/output"
+      compile-bitcode: false
+      upload-bitcode: false
+      upload-symbols: false
       development-team-id: foo
       keychain-path: "/Users/jenkins/Library/Keychains/jenkins-uasdk-ios-pre_review"
       keychain-password: "testpass"