Fortran-language-server

Improvements
* Initial implementation of preprocessor include file handling, ref [115](https://github.com/hansec/fortran-language-server/issues/115)
* Add support for specifying file suffixes for preprocessing, ref [115](https://github.com/hansec/fortran-language-server/issues/115)
* Add support for completion in visibility statements, fixes [120](https://github.com/hansec/fortran-language-server/issues/120)
* Support "onOpen" requests before a file is written to disk, fixes [123](https://github.com/hansec/fortran-language-server/issues/123)
* Add support for IMPURE keyword (contributed by mcocdawc)
* Improve readability by replacing various result arrays with namedtuples

Fixes
* Fix bug in open string literal detection, fixes [124](https://github.com/hansec/fortran-language-server/issues/124)
* Fix bug with multiline docstrings that start with a trailing comment, fixes [118](https://github.com/hansec/fortran-language-server/issues/118)
* Fix symbols types for subroutines and methods in "documentSymbol" and "completion" requests, fixes [117](https://github.com/hansec/fortran-language-server/issues/117)
* Fix bug where ONLY renaming was not fully tracked in some circumstances
* Fix bug with inline dimension specifications for variables
* Fix accidental message swap in "object not found" and "object not imported" diagnostics
* Fix bug where errors were reported with "module subroutine" and "module function" definitions (no import required)

Fixes
* Fix bug in USE ONLY accounting used for graph pruning, fixes [122](https://github.com/hansec/fortran-language-server/issues/122)

Improvements
* Add support for USE statement renaming requests, ref [109](https://github.com/hansec/fortran-language-server/issues/109)
* Add support for argument information in variable hover requests, fixes [107](https://github.com/hansec/fortran-language-server/issues/107)
* Add support for disabling snippets in autocomplete results, fixes [112](https://github.com/hansec/fortran-language-server/issues/112)
* Prevent file AST updates on Open/Close requests when contents have not changed, ref [105](https://github.com/hansec/fortran-language-server/issues/105)
* Reduce unnecessary parsing with single line file changes
* Debugging: Add support for printing full result object

Fixes
* Remove required space between "DOUBLE PRECISION" and "DOUBLE COMPLEX" definitions, fixes [110](https://github.com/hansec/fortran-language-server/issues/110)
* Fix requests when a user-defined type variable has the same name as a defined type used in that scope

Fixes
* Fix parsing single line WHERE statements with trailing parentheses, fixes [106](https://github.com/hansec/fortran-language-server/issues/106)
* Fix erroneous object duplication diagnostics for DO, INTERFACE, etc. blocks
* Remove erroneous "unimplemented procedure" diagnostics from abstract type definitions
* Fix parsing bugs with semicolons in trailing comments

Fixes
* Fix bug with requests in lines with tab characters, fixes [93](https://github.com/hansec/fortran-language-server/issues/93)
* Fix bug with requests following "WRITE(\*,\*)" statements

Improvements
* Add full support for ASSOCIATE statements, fixes [101](https://github.com/hansec/fortran-language-server/issues/101)
* Filter completion suggestions after "MODULE PROCEDURE" statements, fixes [103](https://github.com/hansec/fortran-language-server/issues/103)
* Filter completion suggestions in type-bound procedure links
* Add support for including external source file directories
* Diagnostics: Line length exceeds maximum length errors
* Speedup language server initialization
* Speedup "textDocument/references" requests