Merge compiler notes

We had been maintaining two copies of these notes, this change attempts to
merge them into one set.  The cononical location for these notes is here in
compiler/notes/, they will be removed from the www repository.

I've also updated a number of URLs.

compiler/notes/allocation.html:
compiler/notes/bootstrapping.html:
compiler/notes/coding_standards.html:
compiler/notes/compiler_design.html:
compiler/notes/gc_and_c_code.html:
compiler/notes/glossary.html:
compiler/notes/release_checklist.html:
compiler/notes/reviews.html:
compiler/notes/todo.html:
compiler/notes/work_in_progress.html:
    Merge in differences with the versions of these files in the www
    repository.  Most differences are trivial.

compiler/notes/bytecode.html:
compiler/notes/c_coding_standard.html:
compiler/notes/developer_intro.html:
    Add files that were missing from the main repository but were on the
    website.
Update reviews document

We now use git and github rather than CVS.  I've updated our code review
process document to refer to git and its workflow rather than CVS.

I've also fixed some spelling errors and changed some formatting.

compiler/notes/reviews.html:
    As above.