Update TextMateSharp and syntax highlight using ReadOnlyMemory<char> for reduced allocations

[danipen]

This PR upgrades TextMateSharp from v1.0.x to v2.0.2 and adds ReadOnlyMemory<char> APIs to reduce string allocations during syntax highlighting.

Benchmark Results

See danipen/TextMateSharp#100

Tested with a 133,439 line C# file (5.8 MB):

Metric	master	This PR	Improvement
Execution Time	4.752 s	2.681 s	44% faster
Memory Allocated	658.27 MB	496.36 MB	25% less
Gen0 Collections	82,000	62,000	24% fewer
Gen1 Collections	8,000	4,000	50% fewer

[udlose]

@danipen shouldn't this be bumped?

[Gillibald]

Minimal required version

[udlose]

Minimal required version

@Gillibald
Isn't that property the main version number for AvaloniaEdit? Don't you bump the version number when you release a new version? Or is this not the version number for the AvaloniaEdit nuget package?

[Gillibald]

This is not a release branch, so the version should not be adjusted. If a release is prepared, this needs to be adjusted.

[udlose]

Ok thanks. Will a release be coming? I'm still waiting to get a fix for a bug that was fixed back in May. Much appreciated!

[udlose]

@Gillibald @danipen will there be a release created soon?

[maxkatz6]

@udlose there are nightly builds for AvaloniaEdit, but not automatic. You can use 11.3.999-cibuild0059117-beta, but it doesn't include this PR

[udlose]

@udlose there are nightly builds for AvaloniaEdit, but not automatic. You can use 11.3.999-cibuild0059117-beta, but it doesn't include this PR

Thanks @maxkatz6! seems like a dumb question but how can i access it?

[maxkatz6]

See https://github.com/AvaloniaUI/Avalonia/wiki/Using-nightly-build-feed