Full implementation of DesktopComposeTestRule

[igordmn]

Compose 0.3.2

There are some methods that aren't implemented yet:

waitUntil
registerIdlingResource
unregisterIdlingResource
sendTextInputCommand
sendImeAction
mainClock

[okushnikov]

Please check the following ticket on YouTrack for follow-ups to this issue. GitHub issues will be closed in the coming weeks.