Lot of documentation update, cleaning and formatting.

Almost end of refactoring, except for the JS mode:
- conversion from LiveScript to JavaScript
- import of an isolated module from std (session management)
Worked mostly on the grammar, with a notable change due to the update of PEG.js.

package.json:

- updated PEG.js to the version on GitHub: adding a lot of features

OOP:

- added the possibility to make instances callable: a new property is available when defining the class, giving a method (an actual function) to call in this case
- added the possibility to call generated constructor without the `new` keyword
- fixed processProperties to actually make first argument optional
- exported applyProperties function

STD library:

To fix a problem in registering modes as RPC modules.

- fixed route: now you need to explicitly define the name of a RPC module (the OOP system behind changed indeed)
- added some error messages in rpc

Node:

- changed the interface of the constructor, to use a more object oriented approach (using the oop library). Implied defining some (sub)models
- updated logging methods to use the end offset
- added a development feature to check if a graph covers the entire source code (every character)
- updated the documentation accordingly

Mode:

- fixed highlighting method to properly use the end offset

Grammar:

- added the use of the $ syntax/function: removing library helpers
- updated line, column and offset occurrences to use functions
- added use of the text function
- reduced the initializer because the node instancier is now callable (no need for a wrapper function)

AT Grammar:

- fixed the nonbraced rule: syntax error, `=` was missing
- replaced the helper library references for braces by their unicode representations

HTML Grammar:

- completed coverage of the entire source code, splitting lots of rules, building more nodes (see documentation IN AT MODULE for procedure)

Node instancier (in PEG.js helpers):

- updated to take into account the input source and compute the end offset
- updated to conform to the new Node interface

Tests:

- added the graph coverage test in parsers test
- changed the way to pass data input for test: directly instead of giving a path to compute and read

Parsers (HTML & AT):

- changed the way to build grammars: using an options.json file
- updated the way to use the test utility, reading the data before calling the test
Created a client-side application to visualize a graph generated from parsing.

Application:

- added a public folder at application level to be served
- added routes to serve this application
- updated server options to serve proper static locations

STD library:

- fixed static path resolutions in the server library: to take into account the current working directory instead of the server library directory (which made no sense)

Mode:

- added methods to compute models for graph visualization: libraries-specific