PHP-GSM

Merge pull request #1 in PHP/php-gsm from develop/1.0 to master

* commit 'f22d6c68f7900fb99c5e5d8b008c18bfe833dae3':
  The README
  PDU messaging, pdulib update
  GSM Messaging patch
  Data models for UDH and PDU.
  Composer source
  Method information added
  The copyright
  Unconverted strings removed
  Supporting full send mode (except for the fact that long SMS is still not there)
  Core file is no longer necessary in the public repo
  Now supporting both TEXT and PDU mode, with class 0 SMS in PDU mode
  PDU stuff
  Temporary core file
  PDU update + GSM0338 format file
  GSM library for modems, initial codebase.
  Add some ignores in this space