Optimise get_v_metrics, scale_for_pixel_height

See merge request !21

Optimise get_glyph_h_metrics

See merge request !20

3.5x faster benchmarks

Optimise get_glyph_box

See merge request !19

Optimise find_glyph_index (format=12,13)

See merge request !18

benchmarks 2x faster

deja vu benchmark 1.4x faster

Add benchmark regression tests & gitlab-ci

See merge request !17

Added units_per_em function

Update links to point to redox-os repository

fix: out of bounds read for empty font data

Derive Debug for FontInfo

Bumped byteorder dependency version

Update documentation links, add badges

Implement features for font name strings

RFC 0430 says:

> In `CamelCase`, acronyms count as one word: use `Uuid` rather than
> `UUID`.

(See <https://rust-lang.github.io/rfcs/0430-finalizing-naming-conventions.html#fine-points>.)

Now example correctly handles UTF16BE strings.

Make them public and defined `PlatformEncodingID` type which has
both platform ID and encoding ID.

- if the &[u8] for the font is < 4 bytes, is_font() panics with out of bounds access
- add a length check and return false if the font &[u8] is too short