Adding the 'hitters' dataset.

Author: jdramsey

real/hitters/readme.txt

@@ -1,7 +1,7 @@
 Got the 'hitters' dataset from here:
 
-https://gist.github.com/keeganhines/59974f1ebef97bbaa44fb19143f90bad#file-hitters-csv
+https://gist.githubusercontent.com/keeganhines/59974f1ebef97bbaa44fb19143f90bad/raw/d9bcf657f97201394a59fffd801c44347eb7e28d/Hitters.csv
 
-though it is avialable from many sources.
+though it is available from many sources.
 
-Changing it to tab delimited format and removing the first column (names), though these may be obtained from the above.
+Changing it to tab delimited format and removing the first column (names), though these may be obtained from the above. Using * for missing salaary values.