Bump version to 1.8

Author: jjonescz

src/GtmExtension/source.extension.vsixmanifest

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <PackageManifest Version="2.0.0" xmlns="http://schemas.microsoft.com/developer/vsx-schema/2011" xmlns:d="http://schemas.microsoft.com/developer/vsx-schema-design/2011">
 	<Metadata>
-		<Identity Id="GtmExtension.78062a42-0a99-47d0-a6e2-200a84959b52" Version="1.7" Language="en-US" Publisher="Jan Joneš" />
+		<Identity Id="GtmExtension.78062a42-0a99-47d0-a6e2-200a84959b52" Version="1.8" Language="en-US" Publisher="Jan Joneš" />
 		<DisplayName>Git Time Metric</DisplayName>
 		<Description xml:space="preserve">Git Time Metric plugin for Visual Studio</Description>
 		<MoreInfo>https://github.com/jjonescz/gtm-visualstudio-plugin</MoreInfo>