Xcconfig files are generated for every library target and target 
defined in the Podfile.  However, only the Podfile target xcconfig 
files are added to the user project.  This required tracking all the 
libraries as well as the Podfile targets through the installation and 
integration procedures.

See #971

See #985

Closes #985

Static library targets are created for each combination of user-target
and spec dependency.  This addresses issue #841, although likely not 
entirely.

New command podfile-info - Shows information on installed Pods #855

Added hint about updating CocoaPods installation when Podfile.lock and Manifest.lock are not in sync

Closes #970

Release 0.18.1

* tag '0.18.1':
  Release 0.18.1
  [Fixtures] Update version
  [Changelog]
  Require Core 0.18.1
  Changelog [ci skip]
  [TargetIntegrator] Robustness against target with missing file references
  Fix Xcodeproj autoload
  More autoload #see 919
  Don't initialize Spec::Set::Statistics if not needed
  [Fix] Do not quote `$(inherited)`. Fixes #956.
  [SourceManagers] Fix CocoaPods spelling
  [Rakefile] Set git user on Travis 2
  [Rakefile] Set git user on Travis
  [Installer] Run the hooks of all the specs (not of the installed ones only)

Conflicts:
	CHANGELOG.md
	lib/cocoapods/command.rb

Conflicts:
	CHANGELOG.md