Add Time() and Nanos() methods

[rkuris]

These methods can be used to extract time values
from V1 UUIDs

[coveralls]

Coverage decreased (-1.6%) to 94.946% when pulling 552d1c4 on rkuris:master into 5bf94b6 on satori:master.

[coveralls]

Coverage increased (+0.2%) to 96.751% when pulling a129dcc on rkuris:master into 5bf94b6 on satori:master.

[rkuris]

@satori will you please consider this pull request, or let me know what needs to change to accept it?

[jbsturgeon]

This is a great addition -- We are trying to move away from gocql and this library is the best alternative minus this one missing function.

[rkuris]

@jbsturgeon as this has been oustanding since may, some of us have switched to using a public fork which includes the rollups and the time V1 functions. Please feel free to use the fork at https://github.com/rkuris/go.uuid which also contains a released version 1.2.0 that includes this fix: https://github.com/rkuris/go.uuid/releases/tag/v1.2.0

[coveralls]

Coverage increased (+0.2%) to 95.847% when pulling 009bb7c on rkuris:master into 0633591 on satori:master.

[rkuris]

I've rebased this before, and would be happy to rebase it again if that means it will get accepted.

[michaelrios]

Would love to see this get added :)
Thanks for doing this!

[rkuris]

A bug in the code for this PR has been fixed in gofrs/uuid#31
Strongly recommend moving there, as this repo is not actively maintained.