Bump mathjs from 4.2.2 to 5.9.0

[dependabot-preview]

Bumps mathjs from 4.2.2 to 5.9.0.

Changelog

Sourced from mathjs's changelog.

2019-04-08, version 5.9.0

• Implemented functions row and column (see #1413). Thanks @​SzechuanSage.
• Fixed #1459: engineering notation of function format not available
  for BigNumber.
• Fixed #1465: node.toHTML() not correct for unary operators like
  factorial.

2019-03-20, version 5.8.0

• Implemented new function apply. Thanks @​bnlcas.
• Implemented passing an optional dimension argument to std and var.
  Thanks @​bnlcas.

2019-03-10, version 5.7.0

• Implemented support for pow() in derivative. Thanks @​sam-19.
• Gracefully handle round-off errors in fix, ceil, floor, and range
  (Fixes #1429, see also #1434, #1432). Thanks @​ericman314.

2019-03-02, version 5.6.0

• Upgrade decimal.js to v10.1.1 (#1421).
• Fixed #1418: missing whitespace when stringifying an expression
  containing "not".

2019-02-20, version 5.5.0

• Fixed #1401: methods map and forEach of SparseMatrix not working
  correctly when indexes are unordered.
• Fixed #1404: inconsistent rounding of negative numbers.
• Upgrade tiny-emitter to v2.1.0 (#1397).

2019-01-25, version 5.4.2

• Fixed math.format not working for BigNumbers with a precision above
  1025 digits (see #1385). Thanks @​ericman314.
• Fixed incorrect LaTeX output of RelationalNode. Thanks @​rianmcguire.
• Fixed a bug the methods map, forEach, traverse, and transform
  of FunctionNode.

2019-01-10, version 5.4.1

• Fix #1378: negative bignumbers not formatted correctly.

... (truncated)

Commits

• de3585d Publish v5.9.0
• 87b9a3d Fixed #1459: engineering notation of function format not available for `B...
• c155eb2 Fixed #1465: toHTML() not correct for unary operators
• b716a09 Upgrade to mocha@6.1.1
• c533710 Update codecov to the latest version 🚀 (#1461)
• 089e8ec Update karma-browserstack-launcher to the latest version 🚀 (#1460)
• 8a02eee Update babel7 to the latest version 🚀 (#1458)
• b2a5373 Update uglify-js to the latest version 🚀 (#1457)
• a781636 Revert accidental upgrade to karma-browserstack-launcher@1.4.0
• a3468d1 Update contributor list
• Additional commits viewable in compare view

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[dependabot-preview]

Superseded by #142.