Add file viewer

[oSumAtrIX]

Issue

The apps aims to be a frontend to the GitHub service, but does not offer a file viewer.

Solution

Add a file viewer with support for syntax.

Additional context

A huge QoL feature that the official mobile GitHub app lacks, which is a deal breaker for me at least, is the ability to zoom in or out of the code. You are limited to view the code, line wrapped or not, at a certain font size, but sometimes, you may want to look at a part of the file more closely or see a big overview of the file. Web browsers allow to zoom into sites, including the file viewer of GitHub which is effectively what Materii may want to support natively.

[DarkCrypt]

Wingio is working on file viewing features. Your suggestions should be added to the list, see PR #29.

[oSumAtrIX]

Closing in favour of #29