Delete the pca.c since it's mapreduce now
Add criterion for matrix multiply test case
Add criterion files from kmeans test
Fix a bug of output stream error of mapping file

Previously we open and close the mapping file many times. This may cause
a bug if we use the stdout as the mapping file output. We now open the
mapping file in the runOnModule() function and pass the raw_ostream to
the mapping funtion/file functions.
The default VERSION of matrix multiply is pthread
Change the debug type to giriutil
Delete the useless releaseMemory member function
Rename the STATISTIC and simplify the descriptions
Share the TraceFilename command line option

This option was defined in the CountSrcLines pass of the Utility
directory, and externed in the Giri.cpp and TracingNoGiri.cpp of the
Giri directory. Thus the order of loading the shared object really
matters. We must firstly load the libdgutility.so and then load the
libgiri.so
Refactor the CountSrcLines pass

Now we have a simpler and clean logic and variable names. All this pass
does is to calculate the statistics including number of BBs, number of
ignored instructions, number of source lines, etc.
Refactor the coding style of TraceFile

 - Delete useless interfaces
 - Use the report_fatal_error instead of abort()
 - Rename the variables according to LLVM style
 - Spaces and indent style
 - etc
Add comment for the mmap() of the whole trace file

Also refine some coding styles.
Delete useless findPrevious* member function
Use the report_fatal_error instead of the exit
Refactor the find entry trace member function

Don't need the found variable to hint and return. Just return and report
fatal error at the end of the function.
Remove the useless DFS and EXP-TREE from Giri

Also refine some coding styles.
Refine the comments and variables names in Giri

This is a trivial commit.
Refine the coding of LoadStoreNumbering passes
Refactor the findAllStoresForLoad member function
Consider the tid while find all stores for load

The tid is the pthread identifier to distinguish different threads while
considering a load or store instruction.