Add Greek letters (for math)

[Support for Unicode variable names is nearly universal in modern programming languages](https://rosettacode.org/wiki/Unicode_variable_names). In some languages use of Unicode identifiers is becoming quite widespread, especially using Greek letters in equations to make the notation as similar as possible to that of math & physics. Since the Google Fonts version of Inconsolata lacks Greek letters I often need to temporarily switch to Consolas to read math-oriented packages.

Would it be possible to add Greek letters to Inconsolata? Perhaps the missing glyphs could simply be copied over from [Inconsolata LGC](https://github.com/MihailJP/Inconsolata-LGC) or [Inconsolata-Hellenic](https://github.com/cosmix/Inconsolata-Hellenic). I tried doing so myself but couldn't get the glyph sizes to match, even after syncing Em-size. But I know nothing about font design so hopefully the merge would be straightforward for someone who knows what they are doing.