Use a double for PrecisionModel scale, avoiding overflows

Fixes #652

git-svn-id: http://svn.osgeo.org/geos/branches/3.4@3904 5242fede-7e19-0410-aef8-94bd7d2200fb
Fill up 3.4.2 NEWS section so far

git-svn-id: http://svn.osgeo.org/geos/branches/3.4@3905 5242fede-7e19-0410-aef8-94bd7d2200fb
Fix CAPI version to 1.8.2, and fix a missing c++ version too

git-svn-id: http://svn.osgeo.org/geos/branches/3.4@3906 5242fede-7e19-0410-aef8-94bd7d2200fb