Pin exact dependencies

For applications, it's considered best practices to pin exact versions of dependencies.

This change removes the semantic version range specifiers, and pins each dependency to the maximum allowed by the range specifier. This makes the implicit updates explicit. For example:

- `^1.0.0` will have been upgraded to the maximum minor version available. Equivalent to `1.0.0 <= x < 2.0.0`
- `~1.0.0` will have been upgraded to the maximum patch version available. Equivalent to `1.0.0 <= x < 1.1.0`

.npmrc

@@ -1 +1,2 @@
 unsafe-perm = true
+save-exact = true