Release v0.3.0

The major (breaking) change in this release is the changes made in #56, which is a switch from my private Legendre.jl to the renamed and General.jl-registered AssociatedLegendrePolynomials.jl.

Other minor cleanups and fixes have been included; see the change summary below for details.

What's Changed

• CompatHelper: bump compat for "UnixMmap" to "1" by @github-actions in #57
• Minor cleanups by @jmert in #58
• Fix allocation in pixelcovariance! with pre-allocated work space by @jmert in #59
• Fix test failures seen in recent CI by @jmert in #60
• Fix type promotion error in vec2pix by @jmert in #61
• Follow rename Legendre -> AssociatedLegendrePolynomials by @jmert in #56
• Resolve deprecation warnings from using FileIO by @jmert in #62
• Fix minimum versioning script to handle extras compat bounds by @jmert in #63
• Fix missing doc strings and fix minor typographical errors by @jmert in #64

Full Changelog: v0.2.5...v0.3.0