[RFC] Remove MiNT, NeXTSTEP, OS/2 References

I left just a few OS/2 parts in as they don't necessarily pertain to the platform being supported (credits and syntax definitions).
Good catch, fixed. I remember reading that and thinking it was yet another obscure platform heh.

On November 20, 2014 2:05:47 AM EST, Peter Hajas <notifications@github.com> wrote:
>> @@ -1003,8 +1003,8 @@ The pattern is interpreted like mostly used in
>file names:
>>  	[^ch]   match any character but 'c' and 'h'
>>  
>>  Note that for all systems the '/' character is used for path
>separator (even
>> -MS-DOS and OS/2).  This was done because the backslash is difficult
>to use
>> -in a pattern and to make the autocommands portable across different
>systems.
>> +MS-DOS2). This was done because the backslash is difficult to use in
>a pattern
>
>Potential typo here - MS-DOS2?
>
>---
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