Merge pull request #2 from qgis/manual_en_v2.0

Merge pull request #198 from egonzale/manual_en_v2.0
Merge pull request #3 from qgis/manual_en_v2.0

updates in qgis main repo
review of lessons 7.1 and 7.2
Merge pull request #4 from qgis/manual_en_v2.0

updating my repo
Merge pull request #199 from egonzale/manual_en_v2.0

review of lessons 7.1 and 7.2