Add multi line comment syntax

[imaqtkatt]

No description provided.

[developedby]

Closes #595

[developedby]

I'm not sure about #{ }#.
I understand why but it just looks so ugly.

[developedby]

Every language does this differently, there isn't any common way to do it other than /* */.

If i were to choose, I'd go with #= =# like in julia, even if it doesn't look like it's opening a block, or with #[ ]# like in nim, even if we don't really use [ ] with this kind of meaning elsewhere.

Relevant: https://en.wikipedia.org/wiki/Comparison_of_programming_languages_(syntax)#Comment_comparison

Do you have any preference or reason for any of the options? If not, we'll keep #{ }#

[imaqtkatt]

I slightly would prefer #{ ... #} over #{ ... }#, what do you think?

[developedby]

I slightly would prefer #{ ... #} over #{ ... }#, what do you think?

I like it

[developedby]

Does this also fix #623 ?

[imaqtkatt]

Yes, it does fix the issue