Remove obsolete --cacheDirectory option in README

Looks like it was removed in TypeStrong#701

README.md

@@ -123,7 +123,6 @@ Supports `--print`, `--eval` and `--require` from [node.js CLI options](https://
 _Environment variable denoted in parentheses._
 
 * `-T, --transpile-only` Use TypeScript's faster `transpileModule` (`TS_NODE_TRANSPILE_ONLY`, default: `false`)
-* `--cacheDirectory` Configure the output file cache directory (`TS_NODE_CACHE_DIRECTORY`)
 * `-I, --ignore [pattern]` Override the path patterns to skip compilation (`TS_NODE_IGNORE`, default: `/node_modules/`)
 * `-P, --project [path]` Path to TypeScript JSON project file (`TS_NODE_PROJECT`)
 * `-C, --compiler [name]` Specify a custom TypeScript compiler (`TS_NODE_COMPILER`, default: `typescript`)