1. Disable the MySQL client and LZO library by default when building the Doris.
MySQL client library is used for MySQL external table feature.
This feature will be replaced by the new ODBC external table soon.
LZO library is used to compress/decompress data of some old data format of Doris,
which is no longer used anymore.
2. Add missing license to some files.
3. For all non-Apache-License code, all are explained in NOTICE file and the corresponding license is declared.
4. Remove the js source code from webroot, it will be downloaded as thirdparty
1. reserve `SegmentWriter::_column_writers` before writing it
2. remove some condition branchs in SegmentWriter::init
3. fix hard-coded library names in build-thirdpary.sh
LLVM related codes have already be removed in master branch,
so there is no need to build llvm tool(which need a long
time to compile it).
Currently, some old release of Doris may still need it, so
for now, we just comment it, instead of remove it.
`cmake` has been checked by `check_prerequest`, not needed to check it
twice, and now `CMAKE_CMD` is a command not a file, check it by '-f'
in shell will report an error.
Fix direct compilation failed：
fix compile thirdparty in ubuntu will install libs to lib dir instead of lib64
fix compile error in gcc5 due to the defect of c++11 (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60970)
fix gcc version check will not work on some OS
A bad tablet is always be chosen to do compaction, and failed again
and again, which may block compaction of other tablets.
Add a BE config 'min_compaction_failure_interval_ms' to avoid choosing
bad tablet again at a certain interval, so that other tablets have
chance to do the compaction.
Also fix a bug that using avg() function on varchar column return
unexpected exception.
