Merge pull request #232 from remear/master

Allow the use of mirrors for pip
Remove authorization fee mention, included $5 cap as well as $2 failure fee.
Add best practices section
Merge pull request #235 from remear/best-practices

Add best practices section
ACH debits are no longer in beta
Merge pull request #236 from remear/ach-debit-availability

ACH debits are no longer in beta
Fix js example parameter
Merge pull request #237 from remear/fix-js-example

Fix js example parameter
meta country code uses ISO 3166-1 alpha-3
Merge pull request #238 from remear/country-code

meta country code uses ISO 3166-1 alpha-3
Cleanup
Merge pull request #239 from remear/cleanup

Cleanup
Use customer for overview card charge scenarios
Lock client versions
Merge pull request #240 from remear/fix-scenarios

Fix scenarios
Add format notes to balanced.js expiration arguments
Merge pull request #241 from remear/format-card-expiration

Add format notes to balanced.js expiration arguments
Refer charging a card section to create a debit
Fix missing hold create and capture scenarios
Scenario fixes and updates to use Customer