Make it work on Windows

[Artoria2e5]

Continuing the theme of #724... the global install does not work on Windows without WSL. Node seems to be passing stuff into cmd.

error message

> [email protected] postinstall C:\Users\eleth\AppData\Roaming\npm\node_modules\auspice
> npm run create-data-dir


> [email protected] create-data-dir C:\Users\eleth\AppData\Roaming\npm\node_modules\auspice
> ./scripts/create-data-dir.sh

'.' 不是内部或外部命令，也不是可运行的程序或批处理文件。
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] create-data-dir: `./scripts/create-data-dir.sh`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the [email protected] create-data-dir script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\eleth\AppData\Roaming\npm-cache\_logs\2020-01-30T06_33_48_240Z-debug.log
npm WARN notsup Unsupported engine for [email protected]: wanted: {"node":"10.8.x","npm":"6.2.x"} (current: {"node":"13.3.0","npm":"6.13
.1"})
npm WARN notsup Not compatible with your version of node/npm: [email protected]
npm WARN [email protected] requires a peer of eslint@>= 4.12.1 but none is installed. You must install peer dependencies yourself.
npm WARN [email protected] requires a peer of @types/react@^15.0.0 || ^16.0.0 but none is installed. You must install peer dependencies yourself.
npm WARN [email protected] requires a peer of react@^15.4.2 but none is installed. You must install peer dependencies yourself.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: [email protected] (node_modules\auspice\node_modules\fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current
: {"os":"win32","arch":"x64"})

npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! [email protected] postinstall: `npm run create-data-dir`
npm ERR! Exit status 1

(Yeah I know the error message is all chinese to you. It says '.' is not a command, an executable or a batch file.)

To fix this issue we can probably put "bash" in front of these commands so we are explicitly calling it with bash. This does bring out the additional problem of WSL shipping a binary called "bash" that never errors out. To fix this we can use "env bash" instead -- Cygwin/MSYS always ship with env, and they are 90% percent of the cases where people have a proper bash on Windows anyways.