0.3.1
Don't use pkg-config to check for libev
use symbol list files for building
Add verto_cleanup() to free loaded_modules
Fix rare leak of DSO in module_load
[module] rework module code to its own file with cleanup and docs
Enable (and fix) all warnings
add extern "C" to headers
add verto_set_flags()
Fix tevent autodetection symbol name.
Enforce c89 across codebase