Update changelog

Inhibit warnings by adding search paths as system headers.

[SourcesManager] Ignore repos with unreachable sources on update

Fixes pod lib lint
Closes #1566

Conflicts:
	CHANGELOG.md

Merge branch 'issue_1558_Framework_Search_Paths' of https://github.com/kwales/CocoaPods into kwales-issue_1558_Framework_Search_Paths

* 'issue_1558_Framework_Search_Paths' of https://github.com/kwales/CocoaPods:
  Updated unit tests
  sets framework_search_paths conditionally based on platform
  Changed order of Framework_Search_Paths fixes #1558

Conflicts:
	CHANGELOG.md