Removed chapters

- Removed chapter on testes.tex, content is not relevant
- Removed annex chapter on class diagrams, diagrams are now
included in specs chapter
- Updated makefile to changes
Review in metodologia.tex

- Rewrite of 'testes' and 'implementação' sections
- Added new references on bibliography
Added dns::client class diagram to doc
Review on implementacao.tex
Corrected figure about system architecture