docs(README.md): add troubleshooting tip for syntax errors

[jedwards1211]

as discussed in #903. I had to search for awhile to find that issue and figure out what was going on, and there were some duplicate issues, so I think it would help people to explain this directly in the README.

[codecov]

Codecov Report

Merging #1201 (e4ed5e6) into master (82755eb) will not change coverage.
The diff coverage is n/a.

[cspotcode]

Nice, thanks for writing this up.

We already have this section explaining SyntaxError: https://github.com/TypeStrong/ts-node#syntaxerror
Should your explanation be merged into it?

Should we also explain how to identify the difference between a TypeScript syntax error and a node syntax error? They have different names, so once you know where to look, it's easy and reliable to tell them apart.
I think this may be addressed by merging your additions into the existing SyntaxError section. Perhaps renaming it will also help, something like SyntaxError vs TSError?

[jedwards1211]

I don't think SyntaxError vs TSError would be obvious enough, I had completely failed to notice the SyntaxError section because the name of the errors was the last thing on my mind when I stumbled on this issue. I was thinking "tsc accepted the ?., so why doesn't ts-node?" I thought ts-node was somehow invoking an old version of tsc or using the wrong compile options. So I think some version of "Help! My code compiles with tsc, so why doesn't it work with ts-node?" or "Help! Why am I getting syntax errors in ts-node but not tsc?" is more likely for people to find.

And yeah I think it would be good to merge in what I wrote because I'm not sure the existing explanation there would have been enough to make the light go off in my head. "... cannot be fixed by TypeScript or ts-node. These are runtime issues with your code" sounds like it's saying the mistake is in your code itself, not the transpilation settings.

[jedwards1211]

If nothing else adding Help! to the title would really help, e.g. Help! I'm getting a SyntaxError!, because the Help! catches your eye immediately when you're looking for troubleshooting info.

[jedwards1211]

Okay I merged my explanation into the syntax error section, see what you think

[cspotcode]

Thanks, I haven't forgotten about this. I'm also working on creating a documentation website in #1207

I may roll these changes into a dedicated website page about errors and how to interpret them. Not sure yet; it's all a work-in-progress.
https://typestrong.org/ts-node/docs/interpreting-errors

[cspotcode]

I ended up adding this to the new "Troubleshooting" page: https://typestrong.org/ts-node/docs/troubleshooting#unsupported-javascript-syntax

I'm going to close this to keep the issue tracker tidy, but please feel free to suggest edits or improvements. It's been a while since I've looked at this so I may have neglected something obvious, even if we already discussed it. Thanks again for sending this PR.