Merge branch 'master' into yzf_optimization
Removed duplicate items

Some seemingly different items have the same Name and Exec. We should
regard them as the same and show only one item.
#14 #15 Advanced Search

system commands and commands in the whole filesystem
Final Version

Support 3 types of searching(‘:x’ is too slow as it needs several
minutes for indexing at the first launch. Be careful!)
Merge branch 'yzf_optimization'