Replaced c2s and s2s config pages, removed ssl-config. Made all i18n files have the same line-ending.

Initially, I added a connection type 'admin' that was somewhat abstract. This
poses a practical issue: there's no instantiating an abstract type. As it is
hardly used, it should be removed.

This commit adds ConnectionListener and -Configuration for the webadmin panel.
This required some properties to be optional (where they were not).

This commit (which is compilable, but breaks some important
functionality - work in progess) aims to centralize the configuration
for connections. "Connections" are used in a broad sense here, and
includes socket-based (TLS and legacy-mode SSL) client connections,
BOSH-based client connections, component connections, connectionmanager
(multiplexer) connections, but also connections to the admin panel.

SSLConfig can now be used to get a consistently configured Jetty SSL configuration.

This commit:
- Refactors SSL-related code to reduce complexity and deprecate unused code
- Adds factory methods to obtain SSL/TLS engine / contexts, to replace all
  code duplication that was going on before.

The existing version of BouncyCastle (1.51) presents an issue where while working with more than
one security provider, the BouncyCastle-issued one won't be considered by the JVM. Version 1.53
does not have this problem.

Two out of three arguments in the constructor of the Server Trust Manager
are unused. By deprecating them, calling code can be simplified.

The code to get an instance of SSLContext is duplicated all over the codebase. Code gets more
maintainable by replacing all duplicate code blocks with one utility method.
This already fixes an issue where Clearspace integration used a SSL instead of TLS algorithm.

Update REST API plugin to 1.2.1

Fixed an cluster issue by create a chat room

Extended the github readme

OF-115 Process S2S stanzas from a session serially

Update web.xml schema namespaces to version 3.1 (Java EE 7)

Simplify/improve NIOConnection.deliver() by removing ByteBufferWriter.

For every packet being delivered the `ByteBufferWriter` creates a new String for every few chars written and puts it to the buffer.

According to my tests it is more efficient to create only one string and put it into the buffer once.
(10-20% better performance)

Old version 2.4 was J2EE 1.4

Also remove <taglib> from web.xml. This was required in JSP 1.2, but is no longer in JSP 2.0 (Servlet API 2.4) and gives warnings since it has been removed from the XSD.
See http://wiki.metawerx.net/wiki/RemovingTaglibFromWeb.xml