Add mention of new keybindings to help text and changelog

CHANGELOG.md

@@ -1,5 +1,7 @@
 # Unreleased
 
+- Added keybindings (`0`/`$`) to scroll to left or right side of zoomed-in image ([#131](https://github.com/itsjunetime/tdf/pull/131), thank you [@IshDeshpa](https://github.com/IshDeshpa)!)
+
 # v0.5.0
 
 - Switched simd base64 crate for one that works on stable (from `vb64` to `base64_simd`)

src/tui.rs

@@ -1105,6 +1105,8 @@ gg/G (when on fill-screen):
     Scroll to top/bottom of page
 H, J, K, L (when zoomed in):
     Pan direction around page
+0/$ (when on fill-screen):
+    Scroll to left/right side of page
 ";
 
 pub enum InputAction {