Set up source maps

[Tyriar]

Fixes #354

---

Adds deps exorcist to extract browserify's inline source maps and sorcery to resolve the chain of source maps so that ./dist/xterm.js points at ./src files.

Depends on #353 to fix demo

[parisk]

I am not sure how much does it have to do with this but running npm run build on SourceLair gives me the following logs, which imply some kind of crashing:

Paris@xterm-js:/mnt/project$ npm run build

> [email protected] build /mnt/project
> ./bin/build

error TS5023: Unknown compiler option 'allowJs'.
cpio: ../dist/./addons/fullscreen/fullscreen.css not created: newer or same age version exists
cpio: ../dist/./xterm.css not created: newer or same age version exists
0 blocks
42 blocks

[Tyriar]

I don't expect this if you have typescript 2 installed?

error TS5023: Unknown compiler option 'allowJs'.

This is expected, just a temporary script to recursively copy a file type until we get a proper task runner set up.

cpio: ../dist/./addons/fullscreen/fullscreen.css not created: newer or same age version exists
cpio: ../dist/./xterm.css not created: newer or same age version exists
0 blocks
42 blocks

[parisk]

@Tyriar:

1. 👍 I had a messed-up path and it picked the wrong TypeScript version 😅
2. So I am just ignoring the cpio logs?

[Tyriar]

@parisk yes ignore for now, I suggest we adopt grunt or gulp so that we can get cross-platform builds that encapsulate stuff like this in a nice way. #359

[Tyriar]

@parisk is this good to be merged?

[parisk]

Yep! Sorry for not getting back to this.

[Tyriar]

No worries 😄