Wasmi v0.32 stable release preparations

[Robbepop]

The following list contains the work required before we can release Wasmi v0.32:

• Write Wasmi blog post about the new features and performance improvements.
• Create benchmarking framework to compare Wasmi with other Wasm runtimes.
  • Repository: https://github.com/wasmi-labs/wasmi-benchmarks
• Rename EngineLimits to EnforcedLimits
  • These limits do not just reflect limits of the Wasmi Engine thus the current name is misleading.
  • All checks are currently not even performed in the Engine but rather in the Module. This might change later.
  • PR: Rename EngineLimits to EnforcedLimits #1000
• Rename LinkerBuilder::finish method to create.
  • We are not finalizing the building process since LinkerBuilder is supposed to create multiple Linker instances thus create is the better name.
  • Maybe even introduce a LinkerBuilder::ready -> LinkerBuilderReady method to prevent misusing the LinkerBuilder type statically. Right now LinkerBuilder::{func_wrap, func_new} methods can be used after creation of a Linker but will panic and with another type we could statically enforce correct usage.
  • PR: Make LinkerBuilder type stateful #1001
• Properly mirror the most recent Wasmtime with Store::{get_fuel, set_fuel}.
  • PR: Properly mirror Wasmtime fuel API #1002
• Properly mirror the most recent Wasmtime EngineWeak API.
  • PR: Re-export EngineWeak from the wasmi crate #1003
• Verify that function compilation fuel charging is realistic.
  • PR: Add some malicous translation benchmarks #1005
• Improve Wasmtime API mirroring with minor renamings
  • PR: Improve Wasmi and Wasmtime API mirroring with renamings #1011
• Unify Wasmi workspace crate versions.
  • Makes publishing future Wasmi versions much simpler.
  • PR: Unify Wasmi workspace crate versions #1015