Issue #1955; change loglevel through environment variable
fixes #1955; added a function init_from_env
fixes #1955; minor change
add cscope indexing files at .gitignore
add/modify some comments at the CGaussianLikelihood class
Merge pull request #1965 from dhruv13J/develop

Issue #1955; change loglevel through environment variable
#1931 HSIC unit test added.
Merge pull request #1977 from yorkerlin/develop

add some comments at the CGaussianLikelihood class
Merge pull request #1966 from pl8787/develop

 #1953 memory leak and uninitialised value fixed.
Merge remote-tracking branch 'shogun/develop' into develop
Code format modify.