Gen 1: Better learnsets obtained from Veekun 

Old learnsets were done one by one by volunteers and were afterwards corrected. Change for Veekun obtained learnsets for Gen 1 and Gen 2 so learnsets can be used both for pure Gen 1 and tradebacks Gen 1.
Gen 1: Limit learnsets to not to use tradebacks

Gen 1 learnsets now include all Gen 1 and Gen 2 moves. Limit the moves since pure RBY format does not allow tradeback Pokémon.
Merge pull request #234 from Joimer/patch-21

Gen 1: Better learnsets with no tradebacks