Fix typos, add Telegram contact

Fix typos, including one in documentation that prevented the docs from being
processed and generated into markdown. Added Telegram contact info.

Signed-off-by: Winford <[email protected]>

Author: UncleGrumpy

doc/src/CONTRIBUTING.md

@@ -4,7 +4,7 @@
  SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later
 -->
 
-# Contributing
+# Contributing Guidelines
 
 Make sure to understand the license and the contribution guidelines before contributing and last but not least be kind.
 
@@ -52,8 +52,8 @@ void f(int reverse) {
 
 * Struct names are PascalCase (e.g. Context)
 * Scalar types are lower case (e.g. term)
-* All other names (e.g. functions and variables) are snake_case (e.g. term_is_integer)
-* Always prefix function names (e.g. term_is_nil, term_is_integer, context_new, context_destroy)
+* All other names (e.g. functions and variables) are snake\_case (e.g. term\_is\_integer)
+* Always prefix function names (e.g. term\_is\_nil, term\_is\_integer, context\_new, context\_destroy)
 
 #### Other Coding Conventions
 * Pointer * should be with the variable name rather than with the type (e.g. `char *name`, not `char* name`)

doc/src/welcome-to-atomvm.md

@@ -55,9 +55,9 @@ The [AtomVM Github Repository](https://github.com/atomvm/AtomVM) contains the At
 
 ## Contributing
 
-The AtomVM community welcomes contributions tot he AtomVM code base and upstream and downstream projects.  Please see the [contributing guidelines](../CONTRIBUTING.md) for information about how to contribute.
+The AtomVM community welcomes contributions to the AtomVM code base and upstream and downstream projects.  Please see the [contributing guidelines](CONTRIBUTING.md) for information about how to contribute.
 
-AtomVM developers can be reached on the #AtomVM discord server.
+AtomVM developers can be reached on the #AtomVM discord server or on Telegram at [AtomVM - Erlang and Elixir on Microcontrollers](https://t.me/atomvm).
 
 ## Where to go from here
 

libs/estdlib/src/io_lib.erl

@@ -49,7 +49,7 @@
 %% @doc     Format string and data to a string.
 %%          Approximates features of OTP io_lib:format/2, but
 %%          only supports ~p and ~n format specifiers.
-%%          Raises `badarg` error if the number of format specifiers
+%%          Raises `badarg' error if the number of format specifiers
 %%          does not match the length of the Args.
 %% @end
 %%-----------------------------------------------------------------------------