wikiman: add page (#14922)

Co-authored-by: Wiktor Perskawiec <git@spageektti.cc>
Co-authored-by: Nelson Figueroa <30811275+nelsonfigueroa@users.noreply.github.com>
Co-authored-by: João Pedro Battistella Nadas <joao@dexterenergy.ai>

pages/common/wikiman.md

@@ -0,0 +1,25 @@
+# wikiman
+
+> Offline search engine for documentation.
+> Supports manual pages, Arch Wiki, Gentoo Wiki, FreeBSD documentation, and tldr-pages.
+> More information: <https://github.com/filiparag/wikiman>.
+
+- Search for a specific topic on all installed sources:
+
+`wikiman {{search_term}}`
+
+- Search for a topic in a specific [s]ource:
+
+`wikiman -s {{source}} {{search_term}}`
+
+- Search for a topic in two or more specific [s]ources:
+
+`wikiman -s {{source1,source2,...}} {{search_term}}`
+
+- List existing [S]ources:
+
+`wikiman -S`
+
+- Display [h]elp:
+
+`wikiman -h`