ruby: slicc: allow mathematical operations on Ticks

slicc: improve support for prefix operations

This patch fixes the type handling when prefix operations are used. Previously
prefix operators would assume a void return type, which made it impossible to
combine prefix operations with other expressions. This patch allows SLICC
programmers to use prefix operations more naturally.

ruby: slicc: allow adding a bool to an int, like C++.

ruby: add stats to .sm files, remove cache profiler
This patch changes the way cache statistics are collected in ruby.

As of now, there is separate entity called CacheProfiler which holds
statistical variables for caches. The CacheMemory class defines different
functions for accessing the CacheProfiler. These functions are then invoked
in the .sm files. I find this approach opaque and prone to error. Secondly,
we probably should not be paying the cost of a function call for recording
statistics.

Instead, this patch allows for accessing statistical variables in the
.sm files. The collection would become transparent. Secondly, it would happen
in place, so no function calls. The patch also removes the CacheProfiler class.