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[rbxmdavis]

This fixes issue #9 by duplicating the relevant portion code from
morganwu277@394aac5

I've built an installable extension (.vsix) with this modification and made it available here:
https://github.com/BloxBitBlit/github-linker/blob/release/release/github-linker-0.2.3.vsix

[rbxmdavis]

This pull request also contains additional functionality to immediately open the generated link using the system's URL handler (i.e. browser).

[shrft]

hi. it fails to compile...
npm version: 6.14.4

run this command

npm run vscode:prepublish

then this is resutl.

> tsc -p ./

node_modules/open/index.d.ts:33:36 - error TS1005: ';' expected.

33  	readonly app?: string | readonly string[];
    	                                 ~~~~~~

node_modules/open/index.d.ts:33:43 - error TS1011: An element access expression should take an argument.

33  	readonly app?: string | readonly string[];


node_modules/open/index.d.ts:44:3 - error TS1128: Declaration or statement expected.

44  	readonly url?: boolean;
    	~~~~~~~~

node_modules/open/index.d.ts:44:16 - error TS1109: Expression expected.

44  	readonly url?: boolean;
    	             ~

node_modules/open/index.d.ts:46:1 - error TS1128: Declaration or statement expected.

46 }
   ~

[handonam]

Hi, can we update this PR? If the contributor (@rbxmdavis) isn't available to update conflicts, I can create another PR to base off master, as long as the owner (@gimenete) can acknowledge which is the best path forward.