E3-1504: Add patches fixing memory leaks in epics-base
Changes applied by these patches:
https://github.com/epics-base/epics-base/pull/509
https://github.com/epics-base/epics-base/pull/519
Changes applied by these patches:
https://github.com/epics-base/epics-base/pull/509
https://github.com/epics-base/epics-base/pull/519