Release 2.1.21

Release 2.1.20 (69).

Better support for Stata files (`.do`, `.ado`), fortran (`.f95`) and …

…LaTex (`.cls`) files.

Release 2.1.18.

Support for Crystal and NextFlow languages.

Support for more formats.

Release 2.1.15 (64).

Merge remote-tracking branch 'refs/remotes/origin/master'

Merge remote-tracking branch 'refs/remotes/origin/master'

UI fix.