This commit fixes a few minor issues that Nick and I ran into walking
through some code with the `wasmtime explore` command:
* When a new function is reached the address map iterator is advanced
past the prior function to avoid accidentally attributing instructions
across functions.
* A `<` comparison was changed to `<=` to fix some off-by-one
attributions from instructions to wasm instructions.
* The `skipdata` option is enabled in Capstone to avoid truncating
AArch64 disassemblies too early.
This implements Godbolt Compiler Explorer-like functionality for Wasmtime and
Cranelift. Given a Wasm module, it compiles the module to native code and then
writes a standalone HTML file that gives a split pane view between the WAT and
ASM disassemblies.