modify libtaos.so link

update an expression

fix left/bs for release build

insert into multiple tables with file, return the wrong affected rows

Don't SEGFAULT

Fix compilation of taosdump

Create readme.md

Update pom.xml

Change the pom.xml for the JDBC demo project so that users can directly compile and package an executable jar with all the dependencies.

The mode argument must be supplied when O_CREAT or O_TMPFILE is
specified in flags for open(...).