refactor: split @sapphire/time-utilities into 4 sub-packages (#462)

Co-authored-by: Jeroen Claassens <support@favware.tech>

Author: r-priyam

.all-contributorsrc

@@ -5,9 +5,11 @@
 	"repoHost": "https://github.com",
 	"files": [
 		"packages/async-queue/README.md",
+		"packages/cron/README.md",
 		"packages/decorators/README.md",
 		"packages/discord-utilities/README.md",
 		"packages/discord.js-utilities/README.md",
+		"packages/duration/README.md",
 		"packages/eslint-config/README.md",
 		"packages/event-iterator/README.md",
 		"packages/fetch/README.md",
@@ -19,6 +21,8 @@
 		"packages/snowflake/README.md",
 		"packages/stopwatch/README.md",
 		"packages/time-utilities/README.md",
+		"packages/timer-manager/README.md",
+		"packages/timestamp/README.md",
 		"packages/ts-config/README.md",
 		"packages/utilities/README.md",
 		"README.md"

.eslintignore

@@ -1,5 +1,4 @@
 node_modules/
 **/dist/
 **/docs/
-**/build/
-**/*.d.ts
+**/*.d.ts