Remove swap in activities

What is the current logic behind showing Swap in activities? @hboon

In many cases, it may look like a swap, but actually not. It is impossible to identify all the Swaps without manually pointing them out one by one. If we can not identify all of the Swaps and we may show the wrong Swap, this won't help with clarity and control at all, it just makes the user more confusing.

**Before TokenScript is adopted, I suggest using a standard way to show all the activities titles:
If the contract code is verified on Etherscan, show the activity title as Contract(or DApp) "contract name(contract address if no name)" function "xxxxx"
If the contract code is not verified on Etherscan, show the activity title as Contract(or DApp) "contract name(contract address if no name)" function**

By doing this, at least we know all the information in activities is correct, there won't be any misleading information.

@colourfreak what do you think?