Display the complete compiler output if the compilation failed but the list of errors is empty

see #70
Log compiler process working directory and environment
Fix compilation error with GnuCobol 2.0

Fix #70
#70 Add a test env with GnuCobol 2.0
travis.yml: fix syntax errors not detected by travis linter
#70
debug travis.yml
fix allowed failures
fix typo
Travis CI: Install dev package needed to buil GnuCobol 2.0

#70
Travis CI: fix working dir for running tests and print cobc version before executing tests

#70
Travis CI: fix LD_LIBRARY_PATH

see #70
Travis CI: fix syntax error
travis.yml: cleanup for #70
Fix PEP8 warnings
Strip custom terminal command

This should fix #71
Improve detection of default external terminal on linux
Make use of the new pyqode-console wrapper

This fix issue #68 on linux only (I will have to test that on windows and mac)
This will also help to avoid issue like #71
Fix opening of file where encoding detection failed

Now the editor will show up with the encoding panel visible so that user can reload the editor with another encoding

This commit also fix the encoding cache issue on the cobol backend
Bump version to 4.1.dev
Add pyqode-console support for windows

Finish #68