Add some changelog details for the next release (#61)

Author: ColdHeat

CHANGELOG

@@ -1,6 +1,24 @@
 # Changelog
 
 
+UNRELEASED
+==================
+### Added
+- Added an `extra` field in challenge specification to support different CTFd challenge types
+    - This adds support for dynamic value challenges in CTFd > 3.3.0 (Must have commit df27d0e7a9e336b86165d41920aa176db4ff0e06).
+- Improved `ctf challenge lint` to catch some common mistakes in a challenge
+- Added an `--ignore` flag to `ctf challenge install` and `ctf challenge sync` to disable installation of certain challenge properties (e.g. flags, tags, hints, etc).
+    - Usage: `ctf challenge install challenge.yml --ignore=flags,tags`
+    - Usage: `ctf challenge install --ignore=flags,tags`
+    - Usage: `ctf challenge sync challenge.yml --ignore=flags,tags`
+    - Usage: `ctf challenge sync --ignore=flags,tags`
+
+### Fixed
+- Fix web challenge template for serve.sh
+- Changed all Alpine images in Dockerfiles to use Debian
+- Add examples or more complicated flag creation examples to challenge specification
+
+
 0.0.7 / 2021-04-15
 ==================
 ### Added