Introduce concept of body along with an implementation for string responses.

This is a first step towards deferring response output to the end of the request cycle.

--HG--
extra : source : 923d9676577f3d614b0277b6e1f9557bb48a706d
File server middleware now renders a file body instead of streaming the file content.

We yet have to to ensure that file exists and is readable before rendering the response instead of relying on a FileNotFoundException.

--HG--
rename : src/main/java/com/vtence/molecule/TextBody.java => src/main/java/com/vtence/molecule/StringBody.java
Rework view templates to support deferred output

--HG--
rename : src/main/java/com/vtence/molecule/mustache/JMustacheRenderer.java => src/main/java/com/vtence/molecule/templating/JMustacheRenderer.java
rename : src/main/java/com/vtence/molecule/templating/View.java => src/main/java/com/vtence/molecule/templating/Template.java
rename : src/main/java/com/vtence/molecule/util/Streams.java => src/test/java/com/vtence/molecule/support/Streams.java
rename : src/test/java/com/vtence/molecule/support/Template.java => src/test/java/com/vtence/molecule/support/TemplateRenderer.java
rename : src/test/java/com/vtence/molecule/mustache/JMustacheRendererTest.java => src/test/java/com/vtence/molecule/templating/JMustacheRendererTest.java
rename : src/test/java/com/vtence/molecule/templating/HtmlTemplateTest.java => src/test/java/com/vtence/molecule/templating/TemplatesTest.java
Check that files are readable before opening the stream to prepare for deferred output
Switch compressor codings to set a response body rather than using the output stream.

It is only a first step towards migrating the compressor for deferred output. We'd like to get rid of the buffered output at some point.
Mimic previous behavior and buffer rendering of non-chunked bodies until we complete deferred output.
Let site mesh respond with a decorated body
Remove writer from response
Remove unbuffered output stream from response
Remove buffered output stream from response
Mock response captures, but no longer renders bodies to an internal buffer

--HG--
rename : src/main/java/com/vtence/molecule/BytesBody.java => src/main/java/com/vtence/molecule/BinaryBody.java
rename : src/main/java/com/vtence/molecule/StringBody.java => src/main/java/com/vtence/molecule/TextBody.java
Simple server now defers response output after request processing
We no longer need a buffered response
Use body size rather than content length header value when logging response size
There is no longer a need for resetting the response
A middleware that sets content length header on response with fixed length bodies
Update examples to demonstrate new content length header middleware

--HG--
rename : src/main/java/com/vtence/molecule/middlewares/ContentLength.java => src/main/java/com/vtence/molecule/middlewares/ContentLengthHeader.java
rename : src/test/java/com/vtence/molecule/middlewares/ContentLengthTest.java => src/test/java/com/vtence/molecule/middlewares/ContentLengthHeaderTest.java
Decide on the charset for character bodies at the time of response output
Cover our various body implementations with focused tests
Keep status state in the response