Strip trailing whitespace; add missing newlines.

This promiscuous commit goes around touching almost every file in the
repository with the intention of removing trailing whitespace and adding
newlines to files missing them.

Trailing whitespace has been a pain for along time, especially in terms
of contributing to the project without accidentally littering commits
with whitespace stripping, so this commit is long overdue.

As for the newlines, well, the script I found on StackOverflow to strip
trailing whitespace also happened to add missing newlines, which is
something I wanted to tackle anyway, but in a different commit. It's all
good though.

src/main/resources/plugin.yml

@@ -36,7 +36,7 @@ permissions:
     mobarena.use.ready:
         description: Ready to start the battle
         default: true
-    
+
     mobarena.admin:
         description: Gives access to all admin commands
         default: op
@@ -61,7 +61,7 @@ permissions:
     mobarena.admin.teleport:
         description: Immune to teleport blocking rules.
         default: false
-    
+
     mobarena.setup:
         description: Gives access to all setup commands
         default: op

src/main/resources/res/config.yml

@@ -1,3 +1,3 @@
 global-settings: {}
 classes: {}
-arenas: {}
+arenas: {}

src/main/resources/res/rewards.yml

@@ -6,4 +6,4 @@ waves:
     after:
         '7': minecart, chest_minecart, furnace_minecart
         '13': iron_sword, iron_pickaxe, iron_shovel
-        '16': diamond_sword
+        '16': diamond_sword

src/main/resources/res/settings.yml

@@ -43,4 +43,4 @@ use-scoreboards: true
 isolated-chat: false
 global-join-announce: false
 global-end-announce: false
-show-death-messages: true
+show-death-messages: true

src/main/resources/res/waves.yml

@@ -29,4 +29,4 @@ single:
         wave: 10
         monster: cave_spider
         health: high
-        abilities: arrows, root-target, throw-nearby
+        abilities: arrows, root-target, throw-nearby