Option to use SSL for PushoverHandler (enabled by default), and close connection after sending a message to PushOver.

Solves #146: When sending messages in rapid succession to pushover.net only the first one is sent.
The SSL option is needed when sending messages to users that are not the pushover.net app owner; pushover.net doesn't accept those messages over plain HTTP.
Make ChromePHPHandler and FirePHPHandler sendHeaders flag static so that when multiple instances of the handler class exist they will all respect the one-time check that determines whether the handler should append its logs to the response header
Merge pull request #151 from ryanathasoffers/prevent_erroneosly_sent_FirePHP_and_ChromePHP_header_logs

Fix issue where ChromePHP and FirePHP handlers sent logs to ineligible browsers when >1 handler is instantiated
Merge remote-tracking branch 'AlexButter/master'
Fix permissions
Fix test suite
Update branch-alias
Add BC for the sendHeaders property, fixes #152
Fix idiocy, refs #152