don't force dependencies = TRUE in install_github()
add PR reference to NEWS
Merge pull request #462 from krlmlr/install-github-dependencies

don't force dependencies = TRUE in install_github()
Add line width and limit cores options for check()
Remove extra space
Bump version to 1.5.0.99 for development
Shim help, ?, and system.file on package load

These functions are now inserted into a parent environment of global
when a package is loaded, instead of existing in the devtools package
environment. This is so that the functions are available when a package
is loaded, even if devtools itself is not attached.
Documentation improvements
Update NEWS
Fix shim tests
Don't lock bindings for shims
Fix usage section for help docs
Merge pull request #464 from wch/help-shim

Shim help, ?, and system.file on package load
Fix tests so they work with R CMD check
Remove unnecessary argument
Fixes to help for R CMD check
revdep_check: record package information
Merge pull request #465 from wch/revdep-info

revdep_check: record package information
Properly handle double question mark. Fixes #468
Cleanup help code and add tests