chore: tokens code clean up

[JeneaVranceanu]

Summary of Changes

Only available for review after #704 is merged as they share 1 commit.
Just cleaning some code. Spacing, indents, redundant lines of code like let contract = self.contract.

What has been done:

• removed parameters: [AnyObject](), extraData: Data() from all createReadOperation calls as these are default values;
• added spacing between {} and the code inside;
• removed redundant self. uses;
• removed let contract = self.contract lines;
• and instead of

let tx = contract.createWriteOperation("setAllowance", parameters: [to, value] as [AnyObject] )! return tx 

just returning a result of contract.create....

 

Test Data or Screenshots

 

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