Add more default options on datepicker
Add 1 day on last week option on datepicker
Show device unit on hover label and Y axis
Show last week data on chart start
Remove fixed device name on hover label
Correct misspelled reference
Show localtime on graph X axis and hover label.
Add date offset for localtime on graphdaterange
Device's last updated information on words on index

Device's index shows the last updated information on word instead of a
date.
Use getlocal instead localtime on devices index
Add unit on current value on devices index
Use sampling constant to define number of points on graph
Add apipie for API documentation
Add dropdown menu on navigation bar
Device's unit short to string
Add rails related extensions
Add vendor bundle and rvm config
Add documentation for device's API
Add API documentation for data endpoint
Rename device as datastream across the code

From now on, devices will be refered as datastream. Eventually a device
will represent a collection of datasteams.