Expose PID of the backend process serving a paricular JDBC connection through
a new method in PGConnection interface, analogous to PQbackendPID in libpq C API.
Allow driver to set read-only based on a connection parameter.
Merge pull request #27 from davecramer/master

DbKeyStoreFactory
Merge pull request #25 from rkrzewski/backend_pid

Expose PID of the backend process serving a paricular JDBC connection
Merge pull request #26 from stevenschlansker/read-only

Allow driver to set read-only based on a connection parameter.
Japanese translation spelling corrected provided by Tomonari Katsumata