logs: Limit the number of lines in log files.
logs: Limit the number of lines in log files.

Limits the numbers of lines in log files to 500.

Fixes a part of #727.
zulip/zulip-electron,zulip/zulip-desktop,zulip/zulip-desktop,zulip/zulip-desktop,zulip/zulip-electron,zulip/zulip-electron,zulip/zulip-desktop