使用Cocoapods创建Pod库和私有PodSpec

1、参考：Create-Pod库

2、参考：Create-Private-PodSpec

3、 pod库添加到PodSpec时的坑，参见：GitHub上创建的PodSpecs不能为空

[!] /usr/local/bin/git -C /Users/YourDir/.cocoapods/repos/testSpecs pull

Your configuration specifies to merge with the ref 'refs/heads/master'
from the remote, but no such ref was fetched.