v2.3.0

• Fixed glyphs that overflow the canvas coming out partly zeroed at the clipped right and bottom edges. The distance grids were one buffer too small for them. This mostly hits large glyphs such as some Arabic presentation forms, and emoji under node-canvas (#71 by @cherenkov).
• Sped up SDF generation by about 20%. Output is byte-identical for the default and GL JS settings. With some radius/cutoff combinations, values that land exactly on .5 now round half-to-even instead of up, so a few pixels can differ by ±1.
• Fixed broken output when fontSize or buffer is fractional. buffer is now rounded to an integer.