[pod] Whitelist pods for configurations

An option to only link a specific pod to the target when building in a specific configuration.
The exact syntax is still TBD, pending discussion in https://github.com/CocoaPods/CocoaPods/pull/1668
which implements the corresponding functionality.
[pod] whitelisting: code style and specs
[pod] Whitelist pods for configurations

An option to only link a specific pod to the target when building in a specific configuration.
The exact syntax is still TBD, pending discussion in https://github.com/CocoaPods/CocoaPods/pull/1668
which implements the corresponding functionality.
[pod] whitelisting: code style and specs
[TargetDefinition] Coerce configuration names from user input to strings.
[TargetDefinition] Return list of all configurations for which pods have been whitelisted.
[TargetDefinition] Make predicate method more Ruby-ish.
[TargetDefinition] Also take singular :configuration for whitelisting.
[TargetDefinition] Cleanup docs.
[doc] English, how does it work? /ht @FWDaniel
Use a browser user-agent to validate URLs.
Fix some linting issues.
Bundle: use simplecov 0.9
Bundle: remove documentation group
Not used and created problems on 1.8.7
Rake: fix rubocop task
Bundle: update
RuboCop: autocorrect
RuboCop: update configuration
Updated yaml_helper_spec and yaml_helper to detect merge conflicts with the supplied YAML. Also made distinction on YAMLHelper methods.. i.e. string v file
clean up from previous test adjustments