Merge pull request #2194 from numbbo/release

for release 2.6.3

Merge pull request #2091 from numbbo/release

Bug fix of best_value computation on the constrained linear functions

Merge pull request #2088 from numbbo/release

Release 2.6.1

Merge pull request #2085 from numbbo/release

To be released as v2.6

Merge pull request #2058 from numbbo/release

Corrections in main README.md

Merge pull request #2046 from numbbo/release

Minor correction, allows merge into master with all tests passed.

Merge pull request #1992 from numbbo/development

merge Development into Master for 2.4 release

Merge pull request #1945 from numbbo/development

Merge into master branch for 2.3.3 release

Merge pull request #1938 from numbbo/development

Merge of development branch into master for release 2.3.2