Removing IDE specific ignores

Reasons
- .gitignore contains IDE specific ignores
- IDE specific ignores should be setup using
  global gitignore on local box.
  for eg. create a .gitignore locally and use ...
  git config --global core.excludesfile .gitignore

Changes
- Removed .idea generated by IntelliJ.
- Removed .DS_Store generated by Mac OS.
- Removed .project generated by Eclipse.
- Removed .pydevproject generated by PyDev.
- Removed atlassian-ide-plugin.xml
  generated by Atlassian IDE.

Change-Id: I902e980834716edb8a30ca58df520fd3fc0f73aa
Closes-Bug: #1257279
Updates trove-guestagent.conf.sample

Reason:
- Parameter service_registry_ext has been replaced
  by datastore_registry_ext.
- trove-guestagent.conf.sample contains
  service_registry_ext, should be
  datastore_registry_ext instead.

Changes:
- Updates service_registry_ext to
  datastore_registry_ext in
  trove-guestagent.conf.sample.

Change-Id: I27feb57790011da659f1f2c5e67def08623aa490
Closes-Bug: #1260294
Merge "Updates trove-guestagent.conf.sample"
Merge "Removing IDE specific ignores"