man: add nitc as an alias of nitg

So people that does `man nitc` will see something.

Signed-off-by: Jean Privat <jean@pryen.org>

diff --git a/share/man/man1/nitc.1 b/share/man/man1/nitc.1
new file mode 120000 (symlink)
index 0000000..e213084
--- /dev/null
+++ b/share/man/man1/nitc.1
@@ -0,0 +1 @@
+nitg.1
\ No newline at end of file