Adding ktlint hook to support library.

Additionally, this remove custom gradle tasks to run checkstyle
since this will be handle by repo upload now.

Test: Locally
Change-Id: I8ae6c9eb64680033d750bdf0d8312dd695722ff4
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index ecc61dd..7a349d5 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg
@@ -1,5 +1,6 @@
 [Hook Scripts]
 checkstyle_hook = ${REPO_ROOT}/prebuilts/checkstyle/checkstyle.py --sha ${PREUPLOAD_COMMIT} -c ${REPO_ROOT}/frameworks/support/development/checkstyle/config/support-lib.xml -p development/checkstyle/prebuilt/com.android.support.checkstyle.jar
+ktlint_hook = ${REPO_ROOT}/prebuilts/ktlint/ktlint.py -f ${PREUPLOAD_FILES}
 
 [Builtin Hooks]
 commit_msg_changeid_field = true