Changes in 0.2 since 0.1
* conversion of the buffering system to per-cpu
* update to the liburcu 0.4 API
* upgrade to trace format 2.6; the latest lttv may now be used
* add support for clone() interception in libinterfork
* port refactorings from the kernel tracer up to 0.173
* enhancements/refactor of libustcomm
* add sections in the manual about trace viewing and about tracing apps not linked to libust
* debugging output is now enabled by adding -DUST_DEBUG to the CFLAGS
* usttrace: change ustd socket name to ustd-sock-PID
* change app socket directory name for something more descriptive (/tmp/ust-app-socks)
* code cleanups
* various bug fixes