Migrate to new reflection library

[thekid]

This pull request migrates the code to use xp-framework/reflection. As this changes the API, we will releases this as a major release, 5.0.0 at the time of writing.

Performance

No measurable impact.

Before

$ xp test src/test/php
# ...
Test cases:  156 succeeded
Memory used: 3847.27 kB (3901.40 kB peak)
Time taken:  0.078 seconds (0.159 seconds overall)

After

$ xp test src/test/php
# ...
Test cases:  156 succeeded
Memory used: 3639.90 kB (3694.02 kB peak)
Time taken:  0.079 seconds (0.157 seconds overall)

See also

• Extract reflection to its own library xp-framework/rfc#338
• Remove reflection from XP Core xp-framework/core#332

[thekid]

Released in https://github.com/xp-forge/frontend/releases/tag/v5.0.0