update general_tools.po  JA translation
nearly finished translation
further translations and updated chapter working with projections
Merge pull request #18 from junek/manual_en_v1.8

Manual en v1.8
Merge pull request #82 from dassau/manual_en_v1.8

Manual en v1.8
nearly translated working with projections
Merge pull request #19 from junek/manual_en_v1.8

nearly translated working with projections
Merge pull request #83 from dassau/manual_en_v1.8

Manual en v1.8
Merge branch 'manual_en_v1.8' of https://github.com/qgis/QGIS-Documentation into manual_en_v1.8