Improve variable naming

[matthewjablack]

Description

This PR improves naming throughout the Medianizer and Oracles

Submission Checklist :pencil:

• [x] Rename Medianizer.set to Medianizer.setOracles
• [x] Rename setMax to setMaxReward
• [x] Rename own to deployer
• [x] Rename Medianizer.values to Medianizer.oracles
• [x] Rename Medianizer.push to Medianizer.fund
• [x] Rename Medianizer.val, Medianizer.has to Medianizer.assetPrice, Medianizer.hasPrice
• [x] Rename val, lval to assetPrice, paymentTokenPrice
• [x] Rename min to minOraclesRequired
• [x] Rename zzz, lag to expiry, timeout
• [x] Rename gain to rewardAmount
• [x] Rename Areq, areqs to AsyncRequest, asyncRequests
• [x] Rename owed to rewardee
• [x] Rename pmt, dis to payment, disbursement
• [x] Rename tok to token
• [x] Rename post, tell, posted, told to setAssetPrice, setPaymentTokenPrice, assetPriceSet, paymentTokenPriceSet
• [x] Rename ward to rename
• [x] Rename call to getAssetPrice
• [x] Rename chec to getPaymentTokenPrice
• [x] Rename cur, sup to returnAssetPrice, returnPaymentTokenPrice
• [x] Rename pack to update
• [x] Add glossary to README.md