[WIP] implement Storage APIs. localStorage/sessionStorage

[axetroy]

ref: #1657

depends on: rusty-leveldb

leveldb storage at dir $DENO_DIR/storage/localstorage/:origin

TODO:

• window complatible
• implement domain origin isolation.

eg deno run --origin=example.com xxx.ts ?

• Combine multiple dispatch to one

• if origin does not exist, use pid for isolation

• test case

• Explore possible conflicts caused by using the same origin in multiple processes

eg, there are multiple processes run with this.

deno run --origin=my.domain.com local_storage_set_item.ts

multiple processes write to the same leveldb, which may cause problems

[axetroy]

I contacted the author of rusty-leveldb and hoped to be able to support Window. Before that, temporarily close this PR.

[rektide]

Pardon this is rude and or unhelpful, but I might recommend Sled as the hot new LevelDB-ish replacement that's getting a ton of active development, looks super fast, is cross platform, in general, looks super hip.
https://github.com/spacejam/sled

[kitsonk]

Interesting...