feat(api): add bindings for imgui-knobs (#211)

* feat(api): add bindings for imgui-knobs

Add bindings for the imgui-knobs extension

* Update example/src/main/java/Extra.java

Update styling

Co-authored-by: SpaiR <klimbetoo@gmail.com>

* Update example/src/main/java/Extra.java

Update styling

Co-authored-by: SpaiR <klimbetoo@gmail.com>

* Update .gitignore

Remove gradle.properties from git ignore

* Update styling

Update styling, field names set to UPPER_CASE, remove throwing exceptions from constructors, refactored flags to general style

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Co-authored-by: SpaiR <klimbetoo@gmail.com>

.gitmodules

@@ -22,3 +22,6 @@
 [submodule "include/imgui_club"]
 	path = include/imgui_club
 	url = https://github.com/ocornut/imgui_club
+[submodule "include/imgui-knobs"]
+	path = include/imgui-knobs
+	url = https://github.com/altschuler/imgui-knobs