test: add test samples

Adds test samples that can be used for unit tests or to verify
implementations via:
```bash
for sample in $(ls src/test/resources/samples/*.txt)
do
  echo "Validating $sample"
  rm -f measurements.txt
  ln -s $sample measurements.txt

  diff <(./calculate_average.sh) ${sample%.txt}.out
done
rm measurements.txt
```

For #61

1 files changed, 1 insertions, 0 deletions

diff --git a/src/test/resources/samples/measurements-10.out b/src/test/resources/samples/measurements-10.out
new file mode 100644
index 0000000..f6b787d
--- /dev/null
+++ b/src/test/resources/samples/measurements-10.out
@@ -0,0 +1 @@
+{Adelaide=15.0/15.0/15.0, Cabo San Lucas=14.9/14.9/14.9, Dodoma=22.2/22.2/22.2, Halifax=12.9/12.9/12.9, Karachi=15.4/15.4/15.4, Pittsburgh=9.7/9.7/9.7, Ségou=25.7/25.7/25.7, Tauranga=38.2/38.2/38.2, Xi'an=24.2/24.2/24.2, Zagreb=12.2/12.2/12.2}