Implement template literals and tagged templates

[tofpie]

This Pull Request closes #996.

It changes the following:

• Parsing and lexing of template literals and tagged templates
• New AST nodes for template literals and tagged templates

[codecov]

Codecov Report

Merging #997 (d817a1d) into master (abd893c) will increase coverage by 0.10%.
The diff coverage is 56.55%.

@@            Coverage Diff             @@
##           master     #997      +/-   ##
==========================================
+ Coverage   58.37%   58.47%   +0.10%     
==========================================
  Files         173      176       +3     
  Lines       12050    12225     +175     
==========================================
+ Hits         7034     7149     +115     
- Misses       5016     5076      +60     

Impacted Files	Coverage Δ
...rc/syntax/parser/expression/left_hand_side/call.rs	40.42% <0.00%> (-7.08%)	⬇️
...src/syntax/parser/expression/left_hand_side/mod.rs	90.90% <ø> (ø)
boa/src/syntax/parser/function/mod.rs	63.23% <0.00%> (-0.95%)	⬇️
boa/src/syntax/lexer/template.rs	48.78% <48.64%> (-12.34%)	⬇️
boa/src/syntax/ast/node/mod.rs	47.05% <50.00%> (+0.08%)	⬆️
boa/src/syntax/parser/expression/primary/mod.rs	72.88% <50.00%> (-4.05%)	⬇️
boa/src/syntax/parser/mod.rs	53.57% <50.00%> (-1.99%)	⬇️
boa/src/syntax/lexer/string.rs	53.08% <52.17%> (+14.99%)	⬆️
boa/src/syntax/ast/node/template/mod.rs	53.57% <53.57%> (ø)
.../syntax/parser/expression/left_hand_side/member.rs	69.76% <57.14%> (-2.46%)	⬇️
... and 11 more

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[Razican]

Thank you for the PR!
I have some comments for my understanding mostly, and I have some files left to review. Things are looking very good from a conformance point of view:

Test262 conformance changes:

Test result	master count	PR count	difference
Total	78,497	78,497	0
Passed	24,548	24,698	+150
Ignored	15,585	15,587	+2
Failed	38,364	38,212	-152
Panics	28	30	+2
Conformance	31.27	31.46	+0.19%

[Razican]

I had a bit of time to check more files, looking good. I had some comments, though.

[Razican]

Numbers look great :) there might be a small performance penalty, but this is expected in any new features.

I have reviewed the code, and I didn't see any potential improvement. I would still like for @Lan2u and/or others to review it.

From my side, it can be merged as-is.

[RageKnify]

@tofpie please don't merge master to your PRs unless there are conflicts or you need code that was merged in those commits. It's running all CI again unnecessarily. Wasted CPU time means wasted eletricity.

[tofpie]

OK. Sorry for that.