Update CHANGELOG for 0.1.0

Author: bflad

CHANGELOG.md

@@ -0,0 +1,8 @@
+# 0.1.0 (May 25, 2022)
+
+FEATURES:
+
+* Introduced `float64validator` package with `AtLeast()`, `AtMost()`, and `Between()` validation functions ([#18](https://github.com/hashicorp/terraform-plugin-framework-validators/issues/18))
+* Introduced `int64validator` package with `AtLeast()`, `AtMost()`, and `Between()` validation functions ([#21](https://github.com/hashicorp/terraform-plugin-framework-validators/issues/21))
+* Introduced `stringvalidator.RegexMatches()` validation function ([#23](https://github.com/hashicorp/terraform-plugin-framework-validators/issues/23))
+* Introduced `stringvalidator` package with `LengthAtLeast()`, `LengthAtMost()`, and `LengthBetween()` validation functions ([#22](https://github.com/hashicorp/terraform-plugin-framework-validators/issues/22))