Added VHDL syntax highlighting, and example code. issue #1642
Revert "Added VHDL syntax highlighting, and example code. issue #1642"

This reverts commit 56a37a4053b8ace63eb4d113cb66157a7374b232.
Added VHDL syntax highlighting, and example code. issue #1642
Update vhdl.js

Added license block
Update vhdl_highlight_rules.js

Added license block
Merge pull request #1654 from asm2750/add-vhdl-syntax

Add vhdl syntax