Try shallow clones of submodules

.travis.yml

@@ -17,7 +17,7 @@ before_install:
   - ccache --set-config=compiler_check=content -M 1G -F 0
 
 install:
-  - git clone --depth 1 --recurse-submodules https://github.com/keyboardio/Kaleidoscope-Bundle-Keyboardio ../hardware/keyboardio
+  - git clone --depth 1 --recurse-submodules --shallow-submodules git://github.com/keyboardio/Kaleidoscope-Bundle-Keyboardio ../hardware/keyboardio
 ## We delete the Bundle's version of Kaleidoscope, and symlink ourselves in.
 ## This makes sure we're using the current version of the library.
   - rm -rf ../hardware/keyboardio/avr/libraries/Kaleidoscope