Add apt cheat

Includes apt cheat sheet

cheats/apt.cheat

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+% apt
+
+# Update content listings from package repositories
+apt update
+
+# List all available packages
+apt list
+
+# List all installed packages
+apt list --installed
+
+# Info about package (including description)
+apt show -a <package-name>
+
+# Show versions and archive areas of available package
+apt list -a <package-name>
+
+# Search in repository (packages and description)
+apt search <query>
+
+# Check updates for installed packages
+apt list --upgradeable
+
+# Update all installed packages
+apt upgrade
+
+# Upgrade all installed packages (add/remove dependencies)
+apt full-upgrade
+
+# Update specific/individual package
+apt install --only-upgrade <package-name>
+
+# Downgrade package to a specific version
+apt install <package-name>=<package-version>
+
+# Install a package from repository
+apt install <package-name>
+
+# Remove/delete package
+apt remove <package-name>
+
+# Remove/delete package (with config files)
+apt purge <package-name>
+
+# Install local dpkg package
+apt install <filepath-deb>
+
+# List dependencies of package
+apt depends <package-name>
+
+# List reverse dependencies of package
+apt rdepends <package-name>
+
+# Remove un-needed packages and dependencies
+apt autoremove