FIx: Typo in README
Update README.md

Added a security shield from Hakiri. It shows how secure gem dependencies are.
Merge pull request #1657 from vasinov/master

Update README.md
Merge pull request #1654 from maximeg/patch-1

Fix: Typo in README
Pass options through to the underlying adapter.

Column-specific options can be specified by using its name,
for example:

```
t.attachment :avatar, created_at: { index: true }
```
Refactor previous into its own matcher