Accept file and http URI in the `-f` flag.

This patch was slightly modified to make it merge correctly against
master
(original patch by @jsvd is #1873)

Closes #1873
Added a task to clean the vendor directory

Fixes #1981
Exposing the rake vendor:clean method to the help message

Fixes #1981
Rake way of deleting files

Fixes #1981
bump kibana to 3.1.2

Fixes #2059