- config.h is now search for under PULSE_DIR
- Location of config.h can be specified explicitly with PULSE_CONFIG_DIR
- Extra warning if PULSE_DIR appears to be invalid
* name bootstrap script bootstrap as well as other xrdp repos
* use pkg-config to get pulseaudio version and module directories
* guess prefix by checking for pulseaudio executable
* simplify message then PULSE_DIR not specified
as m4_text_box doesn't support multiple lines