Improve find and rename snapshots functionality

[invidian]

Issue Checklist

• [x] You are submitting: feature request/bug report
• [x] You verified that this is a real problem by searching the [NativeScript Forum] and the other [issues] in this repo.
• [x] You checked our [demo apps] and the [documentation] for sample usage.

Tell us about the problem

I had a problem, with generating snapshots, because it seems that find in https://github.com/NativeScript/nativescript-dev-webpack/blob/master/snapshot/android/project-snapshot-generator.js#L118 is pretty sensitive together with PATH environmental variable. I was getting couple of errors, which later on resulted in application crashes, as it wasn't able to find snapshot file, because they had the wrong name.

I was getting following error:

find: The relative path ‘~/.local/bin’ is included in the PATH environment variable, which is insecure in combination with the -execdir action of find.  Please remove that entry from $PATH

Where for Linux user it's pretty common to have ~/.local/bin in PATH.

It would be cool to make it more environmental-agnostic.

Local environment

• [x] Platform: Linux

Project data

• [x] Platform you are building the app for: Android