Add `nc' tool & adjust finger/spartan to use it

Simple netcat clone, useful for portable scripts. Especially because
some netcats will close the connection as soon as I close stdin... this
one only quits when either stdout or the socket refuses new data.

Also, it uses our standard TCP connection routine, meaning it respects
ALL_PROXY. (i.e. now spartan works with socks5 too)

1 files changed, 6 insertions, 8 deletions

diff --git a/doc/protocols.md b/doc/protocols.md
index 9fa07f06..dbf271bf 100644
--- a/doc/protocols.md
+++ b/doc/protocols.md
@@ -94,19 +94,17 @@ HTML.
 
 ## Finger
 
-Finger is supported through the `adapter/protocol/cha-finger` shell script.
-It is implemented as a shell script because of the protocol's simplicity.
-cha-finger uses the `curl` program's telnet:// protocol to make requests.
-As such, it will not work if `curl` is not installed.
+Finger is supported through the `finger` shell script. It is implemented
+as a shell script because of the protocol's simplicity.
 
-Aspiring protocol adapter writers are encouraged to study cha-finger for
-a simple example of how a custom protocol handler could be written.
+For portability, `finger` uses Chawan's `nc` tool (a very limited netcat
+clone) to make requests.
 
 ## Spartan
 
 Spartan is a protocol similar to Gemini, but without TLS. It is supported
-through the `adapter/protocol/spartan` shell script, which uses `nc` to make
-requests.
+through the `spartan` shell script, and like Finger, it uses Chawan's `nc` to
+make requests.
 
 Spartan has the very strange property of extending gemtext with a
 protocol-specific line type. This is sort of supported through a sed filter