Updates

[marallyn]

Created helper functions:
_formatNumber($number) - parses phone numbers so that user can enter a regular phone number without having to worry about getting the format the way voice wants it.
_get($path) - several methods use a curl get call, so this just standardizes the calls
_getAndParse($path, $isRead = null) - calls _get, then parses the results
_parseGetResults($xml, $isRead = null) - parses the _get results
_post($path, $options) - similar to _get. It just standardizes all the _post calls
_verifyPhoneType($type) - just checks the phone type in a function call rather than defining the array and doing the check in several places

Added arrays:
$_phoneTypes - array of phone types defined in on place rather than all over
$_serverPath - array of server paths rather than hard coding the paths in all the _post and _get calls

Added a couple more methods like archive(), and unarchive()

Grouped the method by what the methods act on (calls, voicemail, sms, all messages)