Added check for all source files to ensure they have no lines longer than 80 chars.

.travis.yml

@@ -1,6 +1,8 @@
 language: rust
 cache:
 - cargo
+before_install:
+- MAX_LINE_LENGTH=80 bash ci/check_line_lengths.sh src/**/*.md
 install:
 - source ~/.cargo/env || true
 - bash ci/install.sh

ci/check_line_lengths.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+
+echo "Checking line lengths in all source files <= $MAX_LINE_LENGTH chars..."
+
+echo "Offending files and lines:"
+(( success = 1 ))
+for file in "$@" ; do
+  echo "$file"
+  (( line_no = 0 ))
+  while IFS="" read -r line || [[ -n "$line" ]] ; do
+    (( line_no++ ))
+    if (( "${#line}" > $MAX_LINE_LENGTH )) ; then
+      (( success = 0 ))
+      echo -e "\t$line_no : $line"
+    fi
+  done < "$file"
+done
+
+(( $success )) && echo "No offending lines found."

ci/install.sh

@@ -1,4 +1,5 @@
 #!/bin/bash
+
 set -ex
 
 function cargo_install() {