Update both 01 and 02 for truffle 4

Updates:

• Update 40%+ of content of 01 and 02.
• Update testing file to match Node ES6 async/await fashion
• Upgrade testrpc(v6.0.3) and truffle(v4.0.1)
• Replied all questions and feedback I received by far

Near Future:

• put tutorials of TokenSale as the priority according to huge readers' demands
• rebrand ethereum-salon

Dreams/wait for the moment

• consider video tutorials
• prepare to launch a friendly course on udemy/youtube late next summer or later.