Move build and test docs to docs repo

See merge request !320

Move and improve upon the build and test docs. Link to the docs in the
README.

bump votepeer lib to version 4.3.752

See merge request !319

cleanup: Fix URL's, update docs

See merge request !318

Add support for importing private key

See merge request nerdekollektivet/votepeer-android-app!317

Also fixes crash issue when viewing mnemonics view introduced in !316

Encapsulate use of mnemonic

See merge request nerdekollektivet/votepeer-android-app!316

This encapsulates use of mnemonic phrase and instead provides a
`getVoterSecret` method.

The use of wallet database is removed by directly deriving the seed from
the mnemonic word list.

Encapsulating mnemonic allows for adding new means to import private
keys, such as private keys imported with WIP.

def votepeer_lib_version = "4.3.751"

See merge request nerdekollektivet/votepeer-android-app!315

targetSdkVersion 32

See merge request nerdekollektivet/votepeer-android-app!314

kotlin 1.6.20

See merge request nerdekollektivet/votepeer-android-app!313

Bump votepeer-library and libbitcoincashkotlin

See merge request nerdekollektivet/votepeer-android-app!312

To get MOV bug fix.

Bump votepeer-lib and libbitcoincash

See merge request nerdekollektivet/votepeer-android-app!311

Adds support for multi-option-vote contract.

Revert "Merge branch 'remove_google_play' into 'master'"

See merge request nerdekollektivet/votepeer-android-app!309

Revert "Merge branch 'debug_apk' into 'master'"

See merge request nerdekollektivet/votepeer-android-app!310

This reverts merge request !305

This reverts merge request !306

Revert "Merge branch 'test_ci' into 'master'"

See merge request nerdekollektivet/votepeer-android-app!308

This reverts merge request !307

test ci

See merge request nerdekollektivet/votepeer-android-app!307

remove google play release

See merge request nerdekollektivet/votepeer-android-app!306

set direct download to debug apk

See merge request nerdekollektivet/votepeer-android-app!305

Update google play page

See merge request nerdekollektivet/votepeer-android-app!303

Update:
* Description
* Short text

Deploy: Update election lifecycle UI

See merge request nerdekollektivet/votepeer-android-app!302

See: https://gitlab.com/nerdekollektivet/votepeer-library/-/merge_requests/307

Update votepeer-lib UI for vote status

See merge request nerdekollektivet/votepeer-android-app!301

`votepeer_lib_version = "4.3.731"`

Update votepeer and libbitcoincash libraries

See merge request nerdekollektivet/votepeer-android-app!300