fix: use custom preview page (preview.vue) if exists

[tosbatti]

Fix issue #100

[tosbatti]

Hi @lihbr, I tried to do the fix but I broke the tests 😅
I moved app definition, because it was needed also before.
Sorry, I suppose the problem is quite simple, but I can't figure out which is.

[lihbr]

Thank you so much @tosbatti! I'll check that out soon and try to publish a patch before the end of the week ☺️

I'll check for the test also 😉

[codecov]

Codecov Report

Merging #101 into master will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #101   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            3         3           
  Lines           48        50    +2     
=========================================
+ Hits            48        50    +2     

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

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[tosbatti]

@lihbr, I found the problem!!! An additional mock was needed for fs.existsSync, as I added a new call.

[lihbr]

Works like a charm now 👌