Update all the transactions and scripts to use prepare/execute and post-conditions

[joshuahannan]

Issue To Be Solved

Many of the transactions in scripts to everything in the prepare block, which is against Cadence best practices
There are also opportunities to include post conditions in many of the transactions to ensure they executed properly

Suggest A Solution

• Split all transactions into prepare/execute when possible
• Add post conditions where possible
• Add additional comments to scripts and transactions if they are not documented