docs: Added docs.

docs/cli/envr_version.md

@@ -0,0 +1,19 @@
+## envr version
+
+Show envr's version
+
+```
+envr version [flags]
+```
+
+### Options
+
+```
+  -h, --help   help for version
+  -l, --long   Show all version information
+```
+
+### SEE ALSO
+
+* [envr](envr.md)	 - Manage your .env files.
+