df_to_examples and create_feature_spec changed
df_to_examples and create_feature_spec changed

Changes made to accommodate int32 type data.
pair-code/what-if-tool,pair-code/what-if-tool,PAIR-code/what-if-tool,pair-code/what-if-tool,PAIR-code/what-if-tool,PAIR-code/what-if-tool,pair-code/what-if-tool,pair-code/what-if-tool,PAIR-code/what-if-tool,PAIR-code/what-if-tool