Revert "found typo"

This reverts commit c66ef2b80b846096e82b423195d1f58f32addb0d.
Revert "forgot to rename a variable"

This reverts commit 4f51dbf175e3a04418d095e91968a4c8fb9c7038.
Revert "made some variable names self describing, corrected a typo"

This reverts commit c5c322f360577add2f1efa9b353bad2936a9b612.
Revert "I added comments for some RBM parameters and a comment in tanh_opt."

This reverts commit ce3c261ab06e76a80ff2c32e6b6382379cd0181a.