preface: Add contributors

+ Adán SDPC (aesedepece)
+ Jordan Baczuk (JBaczuk)
+ María Martín (mmartinbar)

preface.asciidoc

@@ -169,6 +169,7 @@ Many contributors offered comments, corrections, and additions to the early-rele
 
 Following is a list of notable GitHub contributors, including their GitHub ID in parentheses:
 
+* Adán SDPC (aesedepece)
 * Akira Chiku (achiku)
 * Alex Waters (alexwaters)
 * Andrew Donald Kennedy (grkvlt)
@@ -214,6 +215,7 @@ Following is a list of notable GitHub contributors, including their GitHub ID in
 * Jameson Lopp (jlopp)
 * Jason Bisterfeldt (jbisterfeldt)
 * Javier Rojas (fjrojasgarcia)
+* Jordan Baczuk (JBaczuk)
 * Jeremy Bokobza (bokobza)
 * JerJohn15
 * Joe Bauers (joebauers)
@@ -226,6 +228,7 @@ Following is a list of notable GitHub contributors, including their GitHub ID in
 * Magomed Aliev (30mb1)
 * Mai-Hsuan Chia (mhchia)
 * Marco Falke (MarcoFalke)
+* María Martín (mmartinbar)
 * Marzig (marzig76)
 * Matt McGivney (mattmcgiv)
 * Maximilian Reichel (phramz)