feat: manage colors of the focused terminal

Author: polar-fox

releasenotes/notes/feature_manage_colors-3c4e19b536430948.yaml

@@ -0,0 +1,12 @@
+release_summary: >
+  Resetting colors of the current page.
+  Managing background and foreground colors of the current terminal.
+  --reset-colors, --bgcolor-focused, --fgcolor-focused and
+    --reset-colors-focused command line arguments added.
+
+features:
+  - |
+    List new features here followed by the ticket number, for example::
+
+      - Resetting colors of the current page.
+      - Setting of background and foreground colors and resetting colors of the focused terminal.