v0.4.0: Working `.spec` parser in rust arrived!

This release marks the first version of the rpmspec crate.

The versioning starts with v0.4.0 in particular as the crate name on crates.io was actually taken. Fortunately, we have obtained permissions to use the same crate name from the original author of the old crate. Thanks @vv9k!

Since this is basically an entirely different, separate crate, this is 100% incompatible with the previous (<0.4.0) versions.

The crate is still rather unstable, but the following stuff is known to work pretty well, as in, this crate performs better and more accurately compared to other methods (like regex, grep, sed, etc.):

• getting (most) preambles (Requires:, Release:, Version:, etc.)
  • by feeding in an entire spec, all macros in the preambles are expanded.
• getting macro definitions and expanding them (experimental but works 60% of the time?)
• initial %lua support (most lua functions work except compression-related macros (%uncompress)
• most built-in rpm macros
• (kinda broken) parsing entire spec files and getting data for each section (%prep, %files, %changelog, %post`, etc.)

More coming soon!