Added null checks around getting Jira card type

Added null checks around getting card type method in JIRA integration to
fix issue, ZD 30396 Null ref exception in integration service when
creating cards with JIRA,
https://banditsoftware.leankit.com/Boards/View/304368449/305400991
JIRA search was not returning IssueType field.
Fixed GitHub issue link returns 404
Fixed issue with GitHub state to lane mapping
Fixed GitHub search, fixed card not moving when

...state of issue set to open or closed in GitHub
Fixed string comparison issue causing JIRA...

...to attempt to recreate cards that already exist
Fix for default mappings being added when target

type is already mapped to a different LK type
Fixed null issue with card description, and...

...looking up JIRA issue type by LK type name doesn't always work
because the type name is null. So, creating a new card in LeanKit would
always create a bug in JIRA regardless of mapped types.
Adding proxy section to the config.
Fix for creation of new TFS items and better error

fix for creation of new TFS items and better error trapping so an
exception in performing an action based on a LeanKit event does not stop
the event subscriptions from working.
Added support for creating epics in JIRA

This required getting the custom field names and ids from JIRA which is
done through the Custom Fields property. We then set the custom field
for Epic Name when creating or updating an issue.
Adding more logging to JIRA configuration.
Updating LeanKit API client library
Refactored TargetBase to better handle exceptions

for board updates. Added ClientError event logging from the API client.
Fixed bug with moving a task card on to the board
Fixed issue deleting a task card or its parent
Adding DefaultCardCreationLaneId to BoardMapping
Task card event fixes in LeanKit.API.Client
Fixing JIRA issue sync line breaks in description
Updating LeanKit.API.Client.Library