Suppress warnings about events without "emit"

update readme

add afterEach and afterAll hooks

When I first start the Remix IDE, the following warnings are shown in the Compile tab.

```
remix_tests.sol:13:5: Warning: Invoking events without "emit" prefix is deprecated.
    AssertionEvent(result, message);
    ^-----------------------------^
```

To avoid this, add `emit` in front.

Update compiler.js

fix to avoiding duplicate passing or failing tests due to multiple asserts

include filename in contract callback

Allow returning more than one Assert per function

Fix Deploy Libraries

Fix linting

add importFileCb to compiler.js

Export assert lib