Support FreeBSD + ZFS where posix_fallocate reliably returns EINVAL

Dependencies

• [2] M6PHQUGL fallocate only when necessary
• [3] 3CKCVBXT A few optional storable types
• [4] 2ZRCQBXP Version bump
• [5] 4Z4GEJTF Version bump
• [6] YWFYZNLZ Cleanup + inter-process concurrency
• [7] PRDUE4YA Cleanup + published on crates.io
• [8] OP6SVMOD Resetting history
• [9] W2MIZD5B Single file databases + CRC for the root pages (checking the other pages makes everything very slow)
• [10] WTXLZDYI Fixing bus errors on a full disk
• [11] E4MD6T3L Proofreading and commenting of this crate (massive bug fixes included)
• [12] FQ567GAX Version bumps
• [13] RLVQDUPY Fixing a double-free error introduced in 1.2.13
• [14] YXKP4AIW New file locks, with multiple sets of free pages
• [15] OHUZ73MK Versions
• [16] DASFQGOR Debugging
• [17] P5NWMJ2H Version bump
• [18] XOXTGNPZ Adding a contiguous memory allocator (for large blocks)
• [19] TJ2R4HAZ Accessing the root pages (unsafely, of course)
• [20] C36737FJ Arbitrary byte strings, and version 1.3.1

Change contents

• replacement in sanakirja/src/environment/mod.rs at line 3
  [4.1281]→[4.1281:1299](∅→∅)
  − use fs2::FileExt;
  [4.1281]

  [4.21782]
  + use fs4::FileExt;
• replacement in sanakirja/src/environment/mod.rs at line 403
  [2.403]→[2.403:442](∅→∅)
  − file.allocate(length)?;

  − Ok(())
  [2.403]

  [4.5678]
  + if let Err(err) = file.allocate(length) {

  + let code = err.raw_os_error().unwrap();

  +

  + if code == libc::EINVAL {

  + Ok(())

  + } else {

  + Err(err.into())

  + }

  + } else {

  + Ok(())

  + }
• replacement in sanakirja/Cargo.toml at line 23
  [4.7059]→[4.5484:5511](∅→∅),[4.5484]→[4.5484:5511](∅→∅)
  − mmap = [ "memmap", "fs2" ]
  [4.7059]

  [3.651]
  + mmap = [ "memmap", "fs4", "libc" ]
• replacement in sanakirja/Cargo.toml at line 34
  [4.5574]→[4.5574:5617](∅→∅)
  − fs2 = { version = "0.4", optional = true }
  [4.5574]

  [4.7060]
  + fs4 = { version = "0.6.3", optional = true }

  + libc = {version = "0.2", optional = true }