Added new functions

- Renamed interfaces
- Added new functions (ping, encrypt, decrypt, verifyAddress, addBlockWebhook, listBlockWebhooks, removeBlockWebhook)
- Improved some things
- Updated cacert.pem

Fixed toBTC function

- Fixed bug in toBTC function

Added some missing coins

- Added some coins that was missing, but there's still a lot of coins that I'm so lazy to add

Bugfixes

- Fixed user related functions problem
- Converted getWebhookPayload into static function
- Updated sendTransaction example
- Updated receiveWebhook example
- Added sendTransactionToMany example

Bugfixes

Fixed small bugs in some functions
Updated some examples
Added receiveWebhook example

Merge branch 'master' of https://github.com/neto737/BitGoSDK-PHP

Merge branch 'master' of https://github.com/neto737/BitGoSDK-PHP

POST request bugfix

- Fixed bug in POST requests
- Added new example
- Minor improvements

Update composer.json

DELETE method bugfix

- DELETE method bugfix