shell: use rocksdb's histogram for shell key-value size statistics

[acelyc111]

we can see more key/value size statistics now.
the key/value size statistics part of output of shell command count_data -z will look like:

INFO: split[0]: 103800 rows
INFO: split[1]: 68900 rows
INFO: split[2]: 75700 rows
INFO: split[3]: 55200 rows
Count partially, total 303600 rows.

[hash_key_size]
    max = 32
    med = 32.00
    avg = 32.00
    min = 32
    P99 = 32.00
    P95 = 32.00
    P90 = 32.00
[sort_key_size]
    max = 13
    med = 13.00
    avg = 13.00
    min = 13
    P99 = 13.00
    P95 = 13.00
    P90 = 13.00
[value_size]
    max = 155004
    med = 1714.41
    avg = 3233.96
    min = 999
    P99 = 21555.07
    P95 = 11357.16
    P90 = 7609.97
[row_size]
    max = 155049
    med = 1726.63
    avg = 3278.96
    min = 1044
    P99 = 21584.27
    P95 = 11409.80
    P90 = 7662.66

[neverchanje]

其实我意思是在 src/CMakeList.txt 里改...不用 MY_PROJ_INC_PATH

include_directories(${CMAKE_CURRENT_SOURCE_DIR})
include_directories(${CMAKE_CURRENT_SOURCE_DIR}/include)
include_directories(${PEGASUS_PROJECT_DIR}/rocksdb/include)
include_directories(${PEGASUS_ROOT}/include)

+ include_directories(${PEGASUS_PROJECT_DIR}/rocksdb/)

也可以我先过了，以后我再整