"Simplify Pkg2.resolve" Take 2

This reverts commit cc790227cf2bef780dc937d49da0ef9c1fc20578.
doc: fix typo; update helpdb
Fix a problem when removing packages
Merge pull request #3700 from JuliaLang/kf/pkg2

"Simplify Pkg2.resolve" Take 2
add throwto and notify_error, for throwing an exception on the given task,
or waking up waiting tasks with exceptions. fixes #1700
Merge branch 'master' of github.com:JuliaLang/julia
Expand the discussion of abstract types in the FAQ
fix #3395, range[range] indexing bounds checks
Merge branch 'master' of github.com:JuliaLang/julia
First draft at codespeedization of test/perf

To use, run `make codespeed` in `test/perf`
Overhaul of version.jl, removal of COMMIT file, now stores all COMMIT-related information in base/build_h.jl, completely available to julia programs
Changes the contents of `VERSION` to 0.2.0, from 0.2
asd