Refactored Net_SSH2::$identifier and added unit tests

Added return tag
Fixed typo
Rewritten test to just check for possible combinations
Replaced else { if ()...} with elseif() {}
Fixed cs
Fixed missing dataProvider in test
RSA: add unit test for $rsa->loadKey()
SFTP: make get() return correctly sized strings
Merge pull request #237 from terrafrost/sftp-get-size-fix

SFTP: make get() return correctly sized strings

* terrafrost/sftp-get-size-fix:
  SFTP: make get() return correctly sized strings
Merge pull request #236 from terrafrost/rsa-loadkey-unittest

RSA: add unit test for $rsa->loadKey()

* terrafrost/rsa-loadkey-unittest:
  RSA: add unit test for $rsa->loadKey()
Fixed typos
SSH2: add new line in docblock comment
Merge branch 'ssh2-identifier'