Add git attributes file

Add CommandInterface

This will remove the test and docs from when doing a composer install reducing the size of the download and the size on disk

Long option can now be 1 character short

https://github.com/composer/composer/issues/8127

Fix grammar nits

Update packagist description; test with php 7.3

Fix typos

Stop using curly braces for array access

This will be deprecated in php7.4

hhvm is not supported by composer anymore. If the app works in hhvm fine - if not: please install php 7.x for performance boost.

accept any value for options with required argument

This resolves #136

Only for options with optional arguments we have to check if the next argument
is an argument or another option. This allows to start arguments with a hyphen
(or dash `-`) like GNUs `getopt`. For optional arguments starting with a hyphen
you still have to provide them within the argument `--foo=-1`.

do not use default value for counting in set value

update documentation for version 3.2

allow descriptions for operands and show them in a separate table

fix infinite loop with long words in descriptions

(cherry picked from commit 0edf11d0)

(cherry picked from commit fbc18adb)

This solves #127

This fails in #124