Fixed a 'a' to a 'g' in the LR(1) DFA

On page 67, or line 2939 in the tex file
there was an error where an 'a' was supposed to be a 'g'
before the reduction B -> g.
Merge pull request #22 from tbelaire/dfa-fix

Fixed a 'a' to a 'g' in the LR(1) DFA