New way to handle Streams

- Commit for SIPit
Fix assignment.

-- Fails for Firefox
Revert "Fix assignment."

This reverts commit 907f856034461b6531a0e18795de2e15740e5f02.
Revert "New way to handle Streams"

This reverts commit 88fa9b6b2aedbf7d3038362f0e776aed9333980a.
Don't require having 'pegjs' globally installed but check first in ./node_modules.
Added a new grunt task 'all' that compiles grammar, compiles JsSIP and run all the tests.
Small Fix. Reply '200' to a CANCEL 'before' replying 487 to the INVITE

- The order was inverted
Some more love to logs (avoid consecutive logs, instead join them in a single log).
JsSIP.Utils.MD5() renamed to JsSIP.Utils.calculateMD5() (a more proper name for a function).
Added JsSIP.Session#isActive() method.
Revert "Added JsSIP.Session#isActive() method."

This reverts commit c88fbe2ba156aa472a8a362a48b49d6e1a0e5a6a.
Add sips: and tel: scheme support into JsSIP.Utils.normalizeURI and convert them into sip: scheme.
This is useful for the case in which the user clicks in a tel: URI link within a web and the browser is configured to invoke JsSIP as handler of tel: links.
Added one more test.
Enclose every JsSIP component with an inmediate function

- An alement cannot pollute the global namespace
- An element can make use of private variables or methods if required
- Each element has its own 'C' (constant) namespace, if required
Remove RTCPeerConnection.onopen event handler

- The corresponding event has been removed from RTCPeerconnection
Remove the unsuitable method getHeaderUri() from IncomingMessage
Fix. A constant value was being used instead of its reference
Delete hack to quit video description from SDP.

- It is already solved in chrome-stable (Version 25.0.1364.97)
grunt.js refactorized. New 'grunt devel' for faster building (no minified flavor).
Remove TEL visual separators in JsSIP.Utils.normalizeURI() (just if the user portion contains only numbers and visual separators).
Event header parser now converts the "event" field to lowercase.