reads from stdin on wry post with 0 params

[fixes hoop33/wry#43]
describes zero-param behavior in post help, usage
Merge pull request #46 from jeremy-w/feature-post-from-stdin

reads post text from stdin when no params
Issue #38. Add annotations flag to the application object.
Add ChannelCommand to project
Issue #38. Improve annotation output.
Issue #38. Copy annotations parameter from application to service.
Issue #38. Add annotations to User.
Issue #38. Add annotations support for User.
Issue #38. Add annotation support to File, Post, and Message
Close #38. Simply how we specify that we want annotations and combine with count parameter
Issue #38. Include annotations flag in help output.
Issue #38. Put separator after annotations.
Close #44. Add URL and Short URL to file mapping and include appropriately in output.
Add period to end of help text
Issue #41. Add public/private status to File object.
Close #41. Implement Chmod command.
Close #50. Implement Mv command.
Issue #51. Add hashtags and links to posts.
Close #51. Simplify the mapping code and support key paths, not just keys.