Use zprof for profiling startup time (not used by default though).
Load rvm only on demand (reduces zsh startup time by about 0.20s).
Fix autocmd for project-specific configuration.

The exclamation mark in "autocmd!" means that previous autocmds on the
same event are cleared before the new command is added.  This broke the
file type autocmd for C++ standard library headers.
Always use "autocmd", not "au".
Use local variable in OpenUrlUnderCursor() function.
Configure CtrlP to ignore "build" and "bin" directories.
Small improvements to project-specific setup.
Add path to OS X 10.10 SDK, don't define NDEBUG by default.
Add article.
Use tab width of 8 for makefiles.