Add section to docs detailing opening an ST project from the command line.

[AllanLRH]

ST automatically stripped trailing spaces, which creates a lot of "noise" in the diff... but feel welcome to just pick out the part with the section about the command line :)

[aviaryan]

Wow. I had no idea I had left so many trailing spaces. 😅

[aviaryan]

Regarding your addition, I can see that it has been added 2 times. Please fix this.
Also, add it as a point in the FAQ section (last section) and link it in the "Accessing your Notes" section via something like "Learn about opening your notebook via the command line [here]".

[AllanLRH]

I've made some changes — please have another look.

[aviaryan]

Hi @AllanLRH. Thanks for the update.
I have found one more issue, unfortunately. It seems to happen that some trailing spaces were on purpose, like the one in TOC. WIthout that, we have this -

[AllanLRH]

Sorry, I didn't think to check that. Added back some spaces.

[aviaryan]

Thanks for the update @AllanLRH but now you have removed the stuff that this PR is for. Take it easy man! 😄

[AllanLRH]

Haha, wierd! I tried to be smart with git, but was apparently outsmarted.... I tried again, but in a less "clever" way.

[aviaryan]

Thanks!