Move all lua related files to lua/ subfolder

Also remove the lexers sub directory from the Lua search path.
As a result we attempt to open fewer files during startup:

 $ strace -e open -o log ./vis +q config.h && wc -l log

In order to avoid having to modifiy all lexers which `require('lexer')`
we instead place a symlink in the top level directory.

 $ ./configure --disable-lua
 $ rm -rf lua

Should result in a source tree with most lua specifc functionality
removed.

1 files changed, 0 insertions, 59 deletions

diff --git a/lexers/context.lua b/lexers/context.lua
deleted file mode 100644
index 30ec1b0..0000000
--- a/lexers/context.lua
+++ /dev/null
@@ -1,59 +0,0 @@
--- Copyright 2006-2013 Robert Gieseke. See LICENSE.
--- ConTeXt LPeg lexer.
-
-local l = require('lexer')
-local token, word_match = l.token, l.word_match
-local P, R, S = lpeg.P, lpeg.R, lpeg.S
-
-local M = {_NAME = 'context'}
-
--- Whitespace.
-local ws = token(l.WHITESPACE, l.space^1)
-
--- Comments.
-local comment = token(l.COMMENT, '%' * l.nonnewline^0)
-
--- Commands.
-local command = token(l.KEYWORD, '\\' * (l.alpha^1 + S('#$&~_^%{}')))
-
--- Sections.
-local section = token('section', '\\' * word_match{
-  'part', 'chapter', 'section', 'subsection', 'subsubsection', 'title',
-  'subject', 'subsubject', 'subsubsubject'
-})
-
--- ConTeXt environments.
-local environment = token('environment', '\\' * (P('start') + 'stop') * l.word)
-
--- Operators.
-local operator = token(l.OPERATOR, S('$&#{}[]'))
-
-M._rules = {
-  {'whitespace', ws},
-  {'comment', comment},
-  {'environment', environment},
-  {'section', section},
-  {'keyword', command},
-  {'operator', operator},
-}
-
-M._tokenstyles = {
-  environment = l.STYLE_KEYWORD,
-  section = l.STYLE_CLASS
-}
-
-M._foldsymbols = {
-  _patterns = {'\\start', '\\stop', '[{}]', '%%'},
-  ['environment'] = {['\\start'] = 1, ['\\stop'] = -1},
-  [l.OPERATOR] = {['{'] = 1, ['}'] = -1},
-  [l.COMMENT] = {['%'] = l.fold_line_comments('%')}
-}
-
--- Embedded Lua.
-local luatex = l.load('lua')
-local luatex_start_rule = #P('\\startluacode') * environment
-local luatex_end_rule = #P('\\stopluacode') * environment
-l.embed_lexer(M, luatex, luatex_start_rule, luatex_end_rule)
-
-
-return M