version and git helper improvements (#14412)

* Fix up version and git helpers
Improve method names
Move all git calls into the git helper
Allow runtime and external cache of results where appropriate
Consolidate version headers for discovery, poller, and validate

* Style fixes

* improve consistency in git calls

* fix style

* don't send name inconsistently

* Improve database versions

* No need to cache Version it is not used more than once currently.

discovery.php

@@ -64,19 +64,7 @@ if (isset($options['i']) && $options['i'] && isset($options['n'])) {
 }
 
 if (Debug::set(isset($options['d']), false) || isset($options['v'])) {
-    $versions = version_info();
-    echo <<<EOH
-===================================
-Version info:
-Commit SHA: {$versions['local_sha']}
-Commit Date: {$versions['local_date']}
-DB Schema: {$versions['db_schema']}
-PHP: {$versions['php_ver']}
-Database: {$versions['database_ver']}
-RRDTool: {$versions['rrdtool_ver']}
-SNMP: {$versions['netsnmp_ver']}
-==================================
-EOH;
+    echo \LibreNMS\Util\Version::get()->header();
 
     echo "DEBUG!\n";
     Debug::setVerbose(isset($options['v']));