refactor(cli): added equivalent subcommands for each flag combination under every command (#1674)

- image command is now deprecated in favor of 'images'
- cve command is now deprecated in favor of 'cves'

Signed-off-by: Laurentiu Niculae <niculae.laurentiu1@gmail.com>

pkg/cli/cmdflags/flags.go

@@ -0,0 +1,13 @@
+package cmdflags
+
+const (
+	URLFlag          = "url"
+	ConfigFlag       = "config"
+	UserFlag         = "user"
+	OutputFormatFlag = "format"
+	FixedFlag        = "fixed"
+	VerboseFlag      = "verbose"
+	VersionFlag      = "version"
+	DebugFlag        = "debug"
+	SearchedCVEID    = "cve-id"
+)