Improvements
* Add support for find_references, global and top-level module objects only
* Filter autocomplete suggestions for callable objects in call statements
* Speedup initialization and updates on large projects by accelerating construction of USE tree
Fixes
* Fix parser error with definitions requiring enclosing scopes in include files and unnamed programs, fixes [17](https://github.com/hansec/fortran-language-server/issues/17)
* Fix parser failure with visibility statements in included fortran files, fixes [16](https://github.com/hansec/fortran-language-server/issues/16)
* Fix detection of lines with trailing comments