There was no entry in the gitignore file for JetBrains IDEs like PyCharm.
This patch adds an entry to ignore the .idea directory that is created
when the manila-ui git tree is imported as a project into PyCharm.
Change-Id: I27a7793e262bfb234e1cdfc6c674e561f608354b
Create the releasenotes directory and add the requisite
conf.py file to generate manila-ui's release notes.
project-config change: Ibb5e84e621ee0dadd8f6748252536a6447202611
Change-Id: I7a129c47bc3eba904754f4ec8e8140d42b29a0d1