15.1.0

Bug Fixes

• DocumentSpan should attempt to load the source file if it's not loaded yet (#1291) (1eda69c)
• Included symlinked directories when reading a directory (#1290) (f1b4ea2)

Features

• Add Symbol#isOptional method (#1285) (c7f3512)
• Add Type#isTemplateLiteral method (#1288) (284a7fd)