change build target to es5

[bfellows37]

This package has trouble with Internet Explorer 11. The reason is that it uses 'class' syntax and TS will retain that syntax when compiling to ES2015. Compiled to ES5, it works with IE11.

I propose changing the build target to extend support to IE11.

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[bfellows37]

@googlebot I signed it!

[googlebot]

CLAs look good, thanks!

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[Eyas]

Thank you for this!

[bfellows37]

@Eyas out of curiosity, what does your npm publish schedule look like? I notice there have been 3 PRs merged since it was last published.

[Eyas]

@bfellows37 There's no set schedule, but I just published 1.0.2

[bfellows37]

I appreciate it, @Eyas makes my life a little simpler :)