SSL: reworked ngx_ssl_certificate(). This makes it possible to reuse certificate loading at runtime, as introduced in the following patches. Additionally, this improves error logging, so nginx will now log human-friendly messages "cannot load certificate" instead of only referring to sometimes cryptic names of OpenSSL functions.

if exists("b:did_indent")
    finish
endif
let b:did_indent = 1

setlocal indentexpr=

" cindent actually works for nginx' simple file structure
setlocal cindent
" Just make sure that the comments are not reset as defs would be.
setlocal cinkeys-=0#