Use typescript to parse source files

[tmair]

Fixes #54

This pull request uses typescript to construct an AST and find the positions where the require()s should be placed. It should fix several issues and edge cases caused by the regexp approach.

All tests are passing and one new test (adding the possibility to use template literals) was added.

[codecov-io]

Codecov Report

Merging #70 into master will increase coverage by 2.47%.
The diff coverage is 98.78%.

@@            Coverage Diff            @@
##           master     #70      +/-   ##
=========================================
+ Coverage   96.42%   98.9%   +2.47%     
=========================================
  Files           1       1              
  Lines          28      91      +63     
  Branches        5      24      +19     
=========================================
+ Hits           27      90      +63     
  Misses          1       1

Impacted Files	Coverage Δ
index.js	98.9% <98.78%> (+2.47%)	⬆️

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[tmair]

@TheLarkInn I am planning on looking through the issues and see which of them are resolved by this PR. Some of the other PRs already define new tests for the edge cases they fix (based on the regexp approach). So I am planning on adding those tests to the spec as well, just to make sure that the AST approach really covers them

[crhairr]

This would resolve my issue where the regex fails on properly quoted JSON object keys.