Implement create instance from instance template

[Alw3ys]

Implement missing creating of vm instance from template

Fixes #114 🦕

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[codecov]

Codecov Report

Merging #500 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #500   +/-   ##
=======================================
  Coverage   99.61%   99.61%           
=======================================
  Files          22       22           
  Lines       11840    11846    +6     
=======================================
+ Hits        11794    11800    +6     
  Misses         46       46           

Impacted Files	Coverage Δ
src/zone.js	100.00% <100.00%> (ø)

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[sofisl]

Hi @Alw3ys, would you mind adding tests for this method and signing a CLA?

@stephenplusplus, would you mind taking a look at this as well? Thanks in advance!

[stephenplusplus]

Do you like the idea of mapping this to config.template? The createVM() method is trying to be very simple with the terminology, since the Compute API is so complex. I don't think there's another "template" concept the API would expect in this context, so the short hand should be easier to remember and intuitive from this layer.

[Alw3ys]

I'm quite open for other suggestions, The reason I've chosen this way of going forward is since this is how I've seen it in other parts of this repository, and for the sake of keeping consistency, feels quite natural on my eyes to go this way.
Also I would expect something like this to pass the template id, but once again feel free to change it to something that you feel would be a better approach.

[stephenplusplus]

Just to make sure I was being clear, I do think we should support the user passing a template reference for the request, I just thought template would be an easier name on the user to remember/type than sourceInstanceTemplate. As an example of similar shortcuts, config.http expands to {tags: {items: ['http-server']}}. Do you still think the full name the API recognizes is better? (I'm not convinced either way, just honestly interested)

[Alw3ys]

Oh, I didn't understand it properly.
In this case, yes. I do agree with you. I'll push the changes with what you have mentioned :)

[stephenplusplus]

Thank you! It looks perfect to me. I just added a test, but can't push directly. Here's a diff you can apply directly:

$ curl "https://gist.githubusercontent.com/stephenplusplus/6d911fdfdadf904f329c590fc2fb2fdd/raw/8de2d6b201bed3803d21389c5a227661102f3025/compute-pr-500.diff" | git apply

[stephenplusplus]

Thanks again! 🥂

[stephenplusplus]

Released under 2.2.0 👍🏻