Closes #2 : Add -o to fix a broken grep on the bash version in cygwin

cmdarg.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-bashversion=$(bash --version | head -n 1 | grep "version [0-9]" | cut -d ' ' -f 2)
+bashversion=$(bash --version | head -n 1 | grep -o "version [0-9]" | cut -d ' ' -f 2)
 if [ $bashversion -lt 4 ]; then
     echo "cmdarg is incompatible with bash versions < 4.0, please upgrade bash" >&2
     exit 1