doc: fix wrong MySQL version

Reported by _so4. Thanks!!!
test: add test case for optimized between specify outside of key range
Support vector column delimiter change as experimental feature

TODO: write document about mroonga_vector_column_delimiter variable.
Merge pull request #15 from naoa/test-between-over-case

test: add test case for optimized between specify outside of key range

Patch by Naoya Murakami. Thanks!!!
Merge pull request #16 from naoa/add-server-variable-for-vector-delimiter

Support vector column delimiter change as experimental feature

Patch by Naoya Murakami. Thanks!!!
doc: add mroonga_vector_column_delimiter variable
Merge pull request #17 from naoa/doc-mroonga_vector_column_delimiter-variable

doc: add mroonga_vector_column_delimiter variable

Patch by Naoya Murakami. Thanks!!!
rpm: use MySQL 5.6 official repository packages for centos6/7
travis: use latest MariaDB 5.5
Add sh style configuration for Emacs
rpm: remove mysql-mroonga.spec

We dropped support for mysql-server package.
yum: migrate to Vagrant based build system

mysql55-mroonga and mysql56-community-mroonga work.
mariadb-mroonga may work...
yum: add missing dependency for mysql56-cmmunity-mroonga and CentOS 7
yum: re-enable mysql55-mroonga and CentOS 5 i386
yum: fix date
yum: fix variable names
yum: remove needless "."

%{dist} includes ".".
rpm: use ".el7" instead of "%{dist}"

Because "{%dist}" is ".el7.centos". ".centos" is needless.
rpm: remove needless trailing "/"
rpm: fix date