Macros with parameters
[github] Show only own repositories in the checkout dialog.

Don't query and show starred repositories there.

Motivation:
* In contrast with hosted GitHub, GitHub enterprise API doesn't return
  own repositories in /user/starred even if they are starred:
  http://youtrack.jetbrains.com/issue/IDEA-100618#comment=27-445958
  That causes a serious problem that own repositories are unavailable
  in the checkout dialog combobox.
* User can create a repository but not star it, and it won't be listed
  even with hosted GitHub.
* GitHub returns only 30 repositories (IDEA-89630) which causes problems
  and we don't want starred (less important) repositories interfere with
  own (more important) repositories.
[github] Notify about concrete error. IDEA-76963

Instead of just saying "Cannot login with given credentials", show the
exact reason why login has failed.

* Don't catch IOException early (in retrieveCurrentUserInfo), pass it
  through to the GUI clients and show the error in UI: via a Message
  in the Settings; via the error label in GithubLoginDialog; via
  Notifications in other places.
* For this use ThrowableComputable instead of Computable where needed.
* Leave one call untouched as an exception: checkCredentials is designed
  as a quick-check of credentials and connection validity, so let it
  return boolean as it was.
[github] Fix connection timeout value. IDEA-101292

Set connection timeout params on the connection manager instead of
setting them on the client.

Setting these params on the client has no effect, because HttpConnection
is created in HttpMethodDirector#executeMethod, and it inherits params
from the HttpConnectionManager.

Connection parameters are applied to the HttpConnection from
HttpMethod (which inherits them from HttpClient) only AFTER connection
is open, see HttpMethodDirector#executeWithRetry (this.conn.open()
and only then applyConnectionParams()), but the SO_TIMEOUT is already
needed when _opening_ connection.