latex, pdftex, tex, texdoc, texliveonfly, tlmgr: add page (#5294)

pages/common/tlmgr.md

@@ -0,0 +1,32 @@
+# tlmgr
+
+> Manages packages and configuration options of an existing TeX Live installation.
+> More information: <https://www.tug.org/texlive/tlmgr.html>.
+
+- Install a package and its dependencies:
+
+`tlmgr install {{package}}`
+
+- Remove a package and its dependencies:
+
+`tlmgr remove {{package}}`
+
+- Display information about a package:
+
+`tlmgr info {{package}}`
+
+- Update all packages:
+
+`tlmgr update --all`
+
+- Show possible updates without updating anything:
+
+`tlmgr update --list`
+
+- Start a GUI version of tlmgr:
+
+`tlmgr gui`
+
+- List all TeX Live configurations:
+
+`tlmgr conf`