Allow shell quoting on CLI

Break up command-line args using shlex rather than string.split

This enables multiple-word tags using quotes:

mailpile> tag/add "three word tag"
mailpile> tag +"three word tag" 20
Lower the cut-off threshold for tag behavior tracking
Misc fixes to the new route stuff
Add --pidfile flag for writing PID to file
Give /jsapi/ a nice HTML view for debugging and testing
Added missing HTML template
Progress on /jsapi/ and plugins (issue #547)
removed unused import of Unix-only module 'fcntl' from mailpile/crypto/streamer.py
removed unused import of Unix-only module 'fcntl' from mailpile/crypto/symencrypt.py
Added plumbing for Activities (issue #547)
Merge
Fixed so there's no explicit subject on new messages.
Undid previous blooper.
Added json output filter.
Adding support for DNS _pka entries. Closes #522.
Make class naming intuitively illogical (issue #547)
Added support for "data views", implemented in demos.py (issue #547, issue #507)
Unix-only module 'fcntl' is now imported within GnuPG.run within try-except-ImportError to make this module importable under Windows, to allow Windows-developer reimplement GnuPG.run with althouth-Windows modules
import of Unix-only module 'readline' now within try-except-ImportError to make this module importable under Windows
added 'markupsafe' and 'nose' to the required third party packages, but without version number