Update exporter to provide count number of connections for each security association

[breitling200]

Depending on how you configure your IPSEC server, you can have multiple security associations that allow multiple number of connections per security association. You access this data on the command line by typing "ipsec status" or "ipsec statusall" on most major linux platforms such as Ubuntu LTS or CentOS. When you type in that command you will get the output similar to below. The exporter would return the number of "up" security associations that can be queried by prometheus.

Example1:
Security Associations (1 up, 0 connecting):

Example 2:
Security Associations (35 up, 0 connecting):