RETRO 12 - 2017.12

Bug fixes:

- Now builds using GCC (thanks to wuehlmaus in the IRC channel for discovering a bug related to the order of linker arguments when dealing with GCC)
- Now builds on older Ubuntu systems with broken GNU make.

Language Improvements:

- ASCII constants are now using `class:data` (reducing image size by nearly 500 cells and removing call/return overhead when used)
- `s:with-format` now supports \_
- Added `s:split-on-string`
- Added `s:index-of-string`
- Added `s:replace`
- Added `s:tokenize`
- Added `s:tokenize-on-string`

Interfaces:

- *RRE* has significant improvements.

  - Added `gets` to read a string
  - a `unix:` namespace with access to system-specific functionality:

    - `unix:system`
    - `unix:popen` 
    - `unix:pclose`
    - `unix:fork`
    - `unix:wait`
    - `unix:exec0`
    - `unix:exec1`
    - `unix:exec2`
    - `unix:exec3`
    - `unix:getpid`
    - `unix:kill`
    - `unix:getenv`
    - `unix:putenv`
    - `unix:chdir`
    - `unix:write`
    - `unix:sleep`

  - Additions to `f`:

    - `f:sin`
    - `f:cos`
    - `f:tan`
    - `f:asin`
    - `f:acos`
    - `f:atan`

  - Addtions to `file`:

    - `file:spew`

  - Interactive mode (line buffered) when launched with `-i`:

    rre -i

  - Interactive mode (character buffered) when launched with `-c`:

    rre -c

  - When launching with `-i` or `-c` you can also use `-f` to specify
    a file to load:

    rre -c -f filename.ext

  - `bin/listener` now uses `rre` directly and no longer has to copy the RETRO code into a temporary file.

Other:

  - added a c# implementation of the REPL

Documentation:

- Added a `Building.md` with some notes on the build process.
- Fixed formatting issues in the `LICENSE.md` (thanks to Mateusz Piotrowski)
- Added a database (tab separated data) of the words
- Added a `glossary` tool to search, edit, and extract data from the words database

Examples:

- Added `edit.forth`, a functional text/code editor

Final Notes:

Special thanks go to wuehlmaus for his help in testing everything and very useful feedback.