Docs: Update API Table of Contents

Author: phated

docs/api/README.md

@@ -1,19 +1,16 @@
-<!-- front-matter
-id: api-toc
-title: API Table of Contents
-hide_title: true
-sidebar_label: api-toc
--->
+## Table of Contents
 
-## gulp API docs
-
-* [gulp.src](src.md) - Emit files matching one or more globs
-* [gulp.dest](dest.md) - Write files to directories
-* [gulp.symlink](symlink.md) - Write files to symlinks
-* [gulp.task](task.md) - Define tasks
-* [gulp.lastRun](lastRun.md) - Get timestamp of last successful run
-* [gulp.parallel](parallel.md) - Run tasks in parallel
-* [gulp.series](series.md) - Run tasks in series
-* [gulp.watch](watch.md) - Do something when a file changes
-* [gulp.tree](tree.md) - Get the tree of tasks
-* [gulp.registry](registry.md) - Get or set the task registry
+* [API Concepts](concepts.md)
+* [src()](src.md)
+* [dest()](dest.md)
+* [symlink()](symlink.md)
+* [lastRun()](lastRun.md)
+* [series()](series.md)
+* [parallel()](parallel.md)
+* [watch()](watch.md)
+* [task()](task.md)
+* [registry()](registry.md)
+* [tree()](tree.md)
+* [Vinyl](vinyl.md)
+* [Vinyl.isVinyl()](vinyl-isvinyl.md)
+* [Vinyl.isCustomProp()](vinyl-iscustomprop.md)