v0.10.0: Support for ':' and '?' in flow context, fix recent deprecation, various internal improvements

What's Changed

• Fix #309: Not to include \0 in the resulted token by scanBlockScalar by @tom-tan in #310
• fix missing filename in token tests by @Herringway in #313
• add an example app for dumping the tokens of a yaml document by @Herringway in #312
• remove SliceBuilder and Transaction by @Herringway in #315
• don't skip explicit str tags when emitting by @Herringway in #317
• make sure assertEventsEqual() actually has events to test by @Herringway in #316
• remove Loader.parse() by @Herringway in #319
• move Loader.scanBench into benchmark tool by @Herringway in #318
• simplify loader initialization by @Herringway in #320
• replace Mark-esque bits of Scanner.SimpleKey with an actual Mark instead by @Herringway in #321
• implement string representation for tokens by @Herringway in #322
• add more detail to test suite runner by @Herringway in #323
• correct an assert() in Scanner.fetchValue, have it occur earlier by @Herringway in #326
• fix #325 - null simple keys not properly nullified by @Herringway in #327
• support : and ? in flow context as per updated YAML spec by @Herringway in #328
• revamp exception handling by @Herringway in #329
• Fix a DMD 2.109.0 deprecation by @Herringway in #332

Full Changelog: v0.9.2...v0.10.0