Migrate core to TS p2 (#889)

.eslintrc.js

packages/api/.eslintignore

packages/loot-core/package.json

...oot-core/src/platform/client/fetch/__mocks__/index.web.ts

...ages/loot-core/src/platform/client/fetch/index.browser.ts

...ages/loot-core/src/platform/client/fetch/index.testing.ts

packages/loot-core/src/platform/client/fetch/index.web.ts

packages/loot-core/src/platform/client/undo/index.d.ts

packages/loot-core/src/platform/client/undo/index.js

packages/loot-core/src/platform/client/undo/index.web.ts

...t-core/src/platform/server/asyncStorage/index.electron.ts

...ot-core/src/platform/server/asyncStorage/index.testing.ts

...s/loot-core/src/platform/server/asyncStorage/index.web.ts

...ges/loot-core/src/platform/server/connection/index.api.js

...ges/loot-core/src/platform/server/connection/index.api.ts

packages/loot-core/src/platform/server/connection/index.d.ts

...oot-core/src/platform/server/connection/index.electron.ts

...loot-core/src/platform/server/connection/index.testing.js

...loot-core/src/platform/server/connection/index.testing.ts

...ges/loot-core/src/platform/server/connection/index.web.ts