GitLab

* doc/lispref/customize.texi (Common Keywords): Minor clarifications.
Document custom-unlispify-remove-prefixes.
(Variable Definitions): Backquotes in defcustom seem to work fine
now.  Various other copyedits.
(Simple Types): Copyedits.  Document color selector.
(Composite Types): Copyedits.
(Splicing into Lists): Clarifications.