Remove Clike dependency from Bash

The Bash language is actually very different from Clike. Only
'boolean', 'operator' and 'punctuation' are shared between them.
'operator' and 'punctuation' should be changed in the future,
because Bash actually has slightly different operators.

Since they share almost nothing, it makes sense to remove the
dependency. This patch copies 'boolean', 'operator' and
'punctuation' from Clike, but doesn't change them.

This patch also fixes a typo and adds the missing built-in keyword
`let`. `let` is not in the POSIX-standard, but Bash and some other
shells support it.

components.js

@@ -94,7 +94,6 @@ var components = {
 		},
 		"bash": {
 			"title": "Bash",
-			"require": "clike",
 			"owner": "zeitgeist87"
 		},
 		"basic": {

components/prism-bash.js

@@ -1,9 +1,12 @@
 (function(Prism) {
-	var bashVars = {
-		variable: /\$(?:[a-zA-Z0-9_#\?\-\*!@]+|\{[^}]+\})/
-	};
+	var varsRegex = /\$(?:[a-z0-9_#\?\-\*!@]+|\{[^}]+\})/i,
+	    bashVars = { variable: varsRegex };
 
-	Prism.languages.bash = Prism.languages.extend('clike', {
+	Prism.languages.bash = {
+		'shebang': {
+				pattern: /^#!\s*\/bin\/bash|^#!\s*\/bin\/sh/,
+				alias: 'important'
+		},
 		'comment': {
 			pattern: /(^|[^"{\\])#.*/,
 			lookbehind: true
@@ -15,7 +18,7 @@
 			},
 			// Single quote strings cannot have variables inside
 			/'(?:\\?[\s\S])*?'/g,
-			// Support for Here-Dokuments https://en.wikipedia.org/wiki/Here_document
+			// Support for Here-Documents https://en.wikipedia.org/wiki/Here_document
 			{
 				pattern: /(<<\s*)(\w+?)\s*\r?\n(?:[\s\S])*?\r?\n\2/g,
 				lookbehind: true,
@@ -27,17 +30,12 @@
 			pattern: /([^\w\.])-?(0x[\dA-Fa-f]+|\d*\.?\d+([Ee]-?\d+)?)\b/,
 			lookbehind: true
 		},
+		'variable': varsRegex,
 		// Originally based on http://ss64.com/bash/
 		'function': /\b(?:alias|apropos|apt-get|aptitude|aspell|awk|basename|bash|bc|bg|builtin|bzip2|cal|cat|cd|cfdisk|chgrp|chmod|chown|chroot|chkconfig|cksum|clear|cmp|comm|command|cp|cron|crontab|csplit|cut|date|dc|dd|ddrescue|df|diff|diff3|dig|dir|dircolors|dirname|dirs|dmesg|du|egrep|eject|enable|env|ethtool|eval|exec|expand|expect|export|expr|fdformat|fdisk|fg|fgrep|file|find|fmt|fold|format|free|fsck|ftp|fuser|gawk|getopts|git|grep|groupadd|groupdel|groupmod|groups|gzip|hash|head|help|hg|history|hostname|htop|iconv|id|ifconfig|ifdown|ifup|import|install|jobs|join|kill|killall|less|link|ln|locate|logname|logout|look|lpc|lpr|lprint|lprintd|lprintq|lprm|ls|lsof|make|man|mkdir|mkfifo|mkisofs|mknod|more|most|mount|mtools|mtr|mv|mmv|nano|netstat|nice|nl|nohup|notify-send|nslookup|open|op|passwd|paste|pathchk|ping|pkill|popd|pr|printcap|printenv|printf|ps|pushd|pv|pwd|quota|quotacheck|quotactl|ram|rar|rcp|read|readarray|readonly|reboot|rename|renice|remsync|rev|rm|rmdir|rsync|screen|scp|sdiff|sed|seq|service|sftp|shift|shopt|shutdown|sleep|slocate|sort|source|split|ssh|stat|strace|su|sudo|sum|suspend|sync|tail|tar|tee|test|time|timeout|times|touch|top|traceroute|trap|tr|tsort|tty|type|ulimit|umask|umount|unalias|uname|unexpand|uniq|units|unrar|unshar|uptime|useradd|userdel|usermod|users|uuencode|uudecode|v|vdir|vi|vmstat|wait|watch|wc|wget|whereis|which|who|whoami|write|xargs|xdg-open|yes|zip)\b/,
-		'keyword': /\b(if|then|else|elif|fi|for|break|continue|while|in|case|function|select|do|done|until|echo|exit|return|set|declare)\b/
-	});
-
-	Prism.languages.insertBefore('bash', 'keyword', bashVars);
-	Prism.languages.insertBefore('bash', 'comment', {
-		// Shebang must be before comment
-		shebang: {
-			pattern: /^#!\s*\/bin\/bash|^#!\s*\/bin\/sh/,
-			alias: 'important'
-		}
-	});
+		'keyword': /\b(let|if|then|else|elif|fi|for|break|continue|while|in|case|function|select|do|done|until|echo|exit|return|set|declare)\b/,
+		'boolean': /\b(?:true|false)\b/,
+		'operator': /--?|\+\+?|!=?=?|<=?|>=?|==?=?|&&?|\|\|?|\?|\*|\/|~|\^|%/,
+		'punctuation': /[{}[\];(),.:]/
+	};
 })(Prism);