Update bip-0039-wordlists.md

Author: zizelevak

bip-0039/bip-0039-wordlists.md

@@ -7,6 +7,7 @@
 * [Chinese (Traditional)](chinese_traditional.txt)
 * [French](french.txt)
 * [Italian](italian.txt)
+* [Czech](czech.txt)
 
 ##Wordlists (Special Considerations)
 
@@ -81,3 +82,17 @@ Words chosen using the following rules:
 Rules 11 and 12 prevent the selection words that are not different enough. This makes each word more recognizable among others and less error prone. For example: the wordlist contains "atono", then "atomo" is rejected, but "atomico" is good. 
 
 All the words have been manually selected and automatically checked against the rules.
+
+### Czech
+
+Credits: @zizelevak
+
+Words chosen using the following rules:
+
+1.  Words are 4-8 letters long.
+2.  Words can be uniquely determined typing the first 4 letters.
+3.  Only words containing all letters without diacritical marks. (It was the hardest task, because in one third of all Czech letters has diacritical marks.)
+4.  Only nouns, werbs and adverbs, no other word types. All words are in basic form.
+5.  No personal names or geografical names.
+6.  No very similar words with 1 letter of difference.
+7.  No words already used in other language mnemonic sets (english, italian, french, spanish). Letters with diacritical marks from these sets are counted as analogous  letters without diacritical marks.