More work on README

README.md

@@ -3,22 +3,35 @@ Lexesis
 A language agnostic lexical analyser generator
 
 ## Table Of Contents
-* [Introduction][]
-* [Requirements][]
-* [Building][]
-* [Getting started][]
-* [General usage][]
-* [More examples][]
-* [Tested with][]
-* [Authors][]
+* [Introduction](#introduction)
+* [Requirements](#requirements)
+* [Building](#building)
+* [Getting started](#getting-started)
+* [More examples](#more-examples)
+* [Tested with](#tested-with)
+* [Authors](#authors)
 
 ## Introduction
+Lexesis is a language agnostic lexical analyser generator. Which means that it uses a description of *tokens* in the form of regular expressions, and outputs source files for a lexer/scanner (which can be in any language for which a backend has been built, currently only c++), which can be used in building a larger application.
+It's principle is very similar to the well known tools such as [lex](https://en.wikipedia.org/wiki/Lex_(software)) or [flex](http://flex.sourceforge.net), which the difference that Lexesis has a simpler input format, and does not depend on language specific actions to be specified in the configuration file. It uses a programming language independent description of the tokens, in order to allow a bigger reusability across different programming languages of the same lexical analyser specification.
+
+This project came into existence as an application exercise in a course on regular languages and automata for the University of Antwerp.
 
 ## Requirements
 * git
 * CMake 3.2.2+
 * Boost variant header library (needed for mstch)
 
+For those still on *Ubuntu Trusty*, the default cmake version is still 2.8.12, so there is a ppa available with a more up-to-date version.
+
+Run
+```sh
+sudo apt-get update && sudo apt-get -y install software-properties-common; \
+sudo add-apt-repository -y ppa:george-edison55/cmake-3.x; \
+sudo apt-get update && sudo apt-get install -y cmake
+```
+to get this newer version
+
 ## Used dependencies
 The following dependencies will be automatically downloaded with git while building
 
@@ -38,11 +51,10 @@ This will place the Lexesis executable in the `build/bin` folder, with some extr
 You can now simply run `./bin/Lexesis` with the arguments you like (see below and in the man pages for an overview).
 
 ### Running tests
+**TODO**
 
 ## Getting started
 
-## General usage
-See man page?
 
 ### Regular expressions