Add an extra feature (still in the experimental phase) to exclude XCRemoteCache in some SDKs.

e.g. to disable XCRemoteCache for watchOS, a developer can either

• pass --sdks-exclude "watchos*, watchsimulator*" to the xcprepare integrate command or
• set 'exclude_sdks_configurations' => ["watchos*", "watchsimulator*"] to the xcremotecache configuration in Podfile

Implementation

This PR includes:

• Allows disabling remote cache in pre_build with build setting XCRC_DISABLED = YES. This ensures the rebuild script will not unnecessarily download an artifact (if a matching one exists on a remote server) which will not be used. Same for post_build (not not unnecessary upload artifacts) and marking (to not mark artifacts are available).
• Introduces --sdks-exclude param to the CLI integration, which (in the project integration) overrides all XCRC-related params to "" for all SDK configurations listed in an argument
• ^ the same for the cocoapods integration with exclude_sdks_configurations configuration.
• To verify the cocoapods integration (it is the most commonly used scenario), an extra test scenario is added which 1) disables XCRC for "iPhone" SDK and expects 0 hits and 0 misses, 2) disables XCRC for the "WatchOS" SDK and expects 100% hit rate (keep in mind that we build an iPhone app in the test)