Bring file fetching logic into app

[birchamp]

The package shouldn't have to handle this.

[mandolyte]

@PhotoNomad0 Here is my quick and dirty requirements and design spec.

Assumptions:

• All needed repos can be fetched as zip files and stored in indexedDB
• Performance of using the stored zip files is significantly faster than fetching
  • If not we could try other zip reader packages;
  • We only need to read, not write
• Fetching can be conditional based the commit hash of fetched repos

Steps:

• Step one. copy the CV package core book package code into CV app and get it working again
  • [x] all files fetched by CV app
  • [x] file content given to CV pkg to validate
  • [x] results are returned as done currently and then displayed for user
• Step two. unconditionally fetch all needed repos based selected org and language
  • [x] Will need to swap first two Stepper steps: do org/lang picker first, then show books picker
  • [ ] Once org/lang selected then run the preload function to fetch the repos needed
  • [ ] From the repo zip, use the manifest to obtain bible resources (based book id)
• Step three. conditionally fetch all needed repos
  • [ ] Will need to store the commit hash of fetched repos in order to do conditionally fetch
  • [ ] Based on org/lang selection, first check commit hash of each repo
  • [ ] If that repo is already downloaded, do not fetch again
  • [ ] If that repo is not downloaded, then:
  • delete existing out-of-date data plus the stored associated commit hash
  • fetch the repo zip
  • store in indexedDB
  • store the commit hash

[mandolyte]

Today (2020-09-24), I will work on step 1 above, namely: move the book package code from the package into the app and get everything working again.

@PhotoNomad0