Server crashes with spigot Watchdog as below.
Full log attached

[16:07:30] [Spigot Watchdog Thread/ERROR]: The server has stopped responding!
[16:07:30] [Spigot Watchdog Thread/ERROR]: Please report this to http://www.spigotmc.org/
[16:07:30] [Spigot Watchdog Thread/ERROR]: Be sure to include ALL relevant console errors and Minecraft crash reports
[16:07:30] [Spigot Watchdog Thread/ERROR]: Spigot version: git-Spigot-5f38d38-18fbb24 (MC: 1.8.8)
[16:07:30] [Spigot Watchdog Thread/ERROR]: ------------------------------
[16:07:30] [Spigot Watchdog Thread/ERROR]: Server thread dump (Look for plugins here before reporting to Spigot!):
[16:07:30] [Spigot Watchdog Thread/ERROR]: ------------------------------
[16:07:30] [Spigot Watchdog Thread/ERROR]: Current Thread: Server thread
[16:07:30] [Spigot Watchdog Thread/ERROR]: PID: 15 | Suspended: false | Native: false | State: TIMED_WAITING
[16:07:30] [Spigot Watchdog Thread/ERROR]: Stack:
[16:07:30] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.sleep(Native Method)
[16:07:30] [Spigot Watchdog Thread/ERROR]: net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:540)
[16:07:30] [Spigot Watchdog Thread/ERROR]: java.lang.Thread.run(Unknown Source)