Update supported version in SECURITY.md to 0.x.x (#39)

* Update supported version in SECURITY.md to 0.x.x

The latest release is 0.1.0, so the supported version pattern
should be 0.x.x instead of 0.0.x.

* Narrow supported version to 0.1.x and mark 0.0.x unsupported

Using 0.x.x implied backporting security fixes to all minor versions.
Scope to just the current minor series (0.1.x) and explicitly mark
0.0.x as unsupported.

Author: peteski22

SECURITY.md

@@ -12,7 +12,8 @@ The following versions are currently supported for security updates:
 
 | Version | Supported          |
 |---------|--------------------|
-| 0.0.x   | :white_check_mark: |
+| 0.1.x   | :white_check_mark: |
+| 0.0.x   | :x:                |
 
 **Please ensure you are using a supported version when reporting a vulnerability.**