Add minor changes to lang-specific chapters

Signed-off-by: Ekaterina Mekhnetsova <mekkatya@gmail.com>

Author: outoftardis

src/guide/bash.md

@@ -1,4 +1,4 @@
-# Bash guide
+# Bash Guide
 
 ## 0. A brief primer on CLI applications
 

src/guide/javascript.md

@@ -1,4 +1,4 @@
-# JavaScript / TypeScript guide
+# JavaScript/TypeScript Guide
 
 ::: info
 

src/guide/kotlin-java.md

@@ -1,4 +1,4 @@
-# Kotlin/Java guide
+# Kotlin/Java Guide
 
 ## 1. Iroha 2 Client Setup
 

src/guide/python.md

@@ -1,4 +1,4 @@
-# Python 3 guide
+# Python 3 Guide
 
 ::: warning
 

src/guide/rust.md

@@ -158,8 +158,8 @@ characters into a nice small table of obviously hexadecimal numbers.
 
 ::: warning
 
-**BEWARE**: Even the `try_from_str` implementation cannot verify if a given
-string is a valid `PrivateKey` and warn you if it isn't.
+Even the `try_from_str` implementation cannot verify if a given string is a
+valid `PrivateKey` and warn you if it isn't.
 
 It will catch some obvious errors, e.g. if the string contains an invalid
 symbol. However, since we aim to support many key formats, it can't do much