Update NEWS for upcoming 7.9.0 release

Merge pull request #1401 from tpaviot/review/prepare-7.8.1.1

Review/prepare 7.8.1.1

Typo in CMakeLists

minor changes in INSTALL and README

Merge pull request #1160 from tpaviot/review/occt770

Port to occt770

Merge pull request #1133 from tpaviot/review/occt762

wrapper for occt7.6.2

Prepare release 7.5.1

Set version number to 7.5.0rc1

update generator.log

prepare release 7.4.0