add openCover script to support open:cover command on windows

[deanbot]

see issue #395

[coveralls]

Coverage remained the same at 95.283% when pulling 0530534 on deanbot:master into 500371e on coryhouse:master.

[RoM4iK]

Why no ./node_modules/.bin/open ./coverage/lcov-report/index.html in package.json?
I think its better to avoid creation of new file in tools unless its necessary.

[deanbot]

Hi @RoM4iK, open isn't in ./node_modules/.bin/. That being said if you know another way to call open (i.e. open('./coverage/lcov-report/index.html') in package.json without an additional script all the better.

[RoM4iK]

Then, we can move to a better opener package, instead of writing wrappers for existing.
We can look at opn, and exactly on opn-cli

[coryhouse]

Ah good idea @RoM4iK. I wasn't aware of opn-cli, but it looks perfect. @deanbot - Would you be willing to adjust your PR to use it?

[deanbot]

No problem.

[coveralls]

Coverage remained the same at 95.283% when pulling 5b1c14b on deanbot:master into 500371e on coryhouse:master.

[coryhouse]

Thanks! 👍