fix hashing and marker detection and make specs more explicit

[thescientist13]

Related Issue

resolves #572

Summary of Changes

Ooof, a couple things going on here that we not properly implemented (my bad)

1. Hashing was not implemented correctly and not really generating unique IDs, so copied over hashing function from graphql (for now)
2. Fixed marker detection logic

TODOs

1. Check for other inline cases of plain <script> and <style>, add specs as needed
2. eve-container module not being bundled now
3. Should make an issue to make sure <style>/* code */ and <script>/* code */</style> are getting optimized / minified - ensure inline <script> and <style> tags are getting minified / optimized when running build command #581
4. I think this might be the root cause of [demo / bug] inline optimization is broken on subsequent page load #495, should see if it helps after this is merged