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, 88 deletions

diff --git a/lexers/rust.lua b/lexers/rust.lua
deleted file mode 100644
index 60834fb..0000000
--- a/lexers/rust.lua
+++ /dev/null
@@ -1,88 +0,0 @@
--- Copyright 2015-2016 Alejandro Baez (https://keybase.io/baez). See LICENSE.
--- Rust 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 = 'rust'}
-
--- Whitespace.
-local ws = token(l.WHITESPACE, l.space^1)
-
--- Comments.
-local line_comment = '//' * l.nonnewline_esc^0
-local block_comment = '/*' * (l.any - '*/')^0 * P('*/')^-1
-local comment = token(l.COMMENT, line_comment + block_comment)
-
--- Strings.
-local sq_str = P('L')^-1 * l.delimited_range("'")
-local dq_str = P('L')^-1 * l.delimited_range('"')
-local raw_str =  '#"' * (l.any - '#')^0 * P('#')^-1
-local string = token(l.STRING, dq_str + raw_str)
-
--- Numbers.
-local number = token(l.NUMBER, l.float + (l.dec_num + "_")^1 +
-                     "0b" * (l.dec_num + "_")^1 + l.integer)
-
--- Keywords.
-local keyword = token(l.KEYWORD, word_match{
-  'abstract',   'alignof',    'as',       'become',   'box',
-  'break',      'const',      'continue', 'crate',    'do',
-  'else',       'enum',       'extern',   'false',    'final',
-  'fn',         'for',        'if',       'impl',     'in',
-  'let',        'loop',       'macro',    'match',    'mod',
-  'move',       'mut',        "offsetof", 'override', 'priv',
-  'proc',       'pub',        'pure',     'ref',      'return',
-  'Self',       'self',       'sizeof',   'static',   'struct',
-  'super',      'trait',      'true',     'type',     'typeof',
-  'unsafe',     'unsized',    'use',      'virtual',  'where',
-  'while',      'yield'
-})
-
--- Library types
-local library = token(l.LABEL, l.upper * (l.lower + l.dec_num)^1)
-
--- syntax extensions
-local extension = l.word^1 * S("!")
-
-local func = token(l.FUNCTION, extension)
-
--- Types.
-local type = token(l.TYPE, word_match{
-  '()', 'bool', 'isize', 'usize', 'char', 'str',
-  'u8', 'u16', 'u32', 'u64', 'i8', 'i16', 'i32', 'i64',
-  'f32','f64',
-})
-
--- Identifiers.
-local identifier = token(l.IDENTIFIER, l.word)
-
--- Operators.
-local operator = token(l.OPERATOR, S('+-/*%<>!=`^~@&|?#~:;,.()[]{}'))
-
--- Attributes.
-local attribute = token(l.PREPROCESSOR, "#[" *
-                        (l.nonnewline - ']')^0 * P("]")^-1)
-
-M._rules = {
-  {'whitespace', ws},
-  {'keyword', keyword},
-  {'function', func},
-  {'library', library},
-  {'type', type},
-  {'identifier', identifier},
-  {'string', string},
-  {'comment', comment},
-  {'number', number},
-  {'operator', operator},
-  {'preprocessor', attribute},
-}
-
-M._foldsymbols = {
-  _patterns = {'%l+', '[{}]', '/%*', '%*/', '//'},
-  [l.COMMENT] = {['/*'] = 1, ['*/'] = -1, ['//'] = l.fold_line_comments('//')},
-  [l.OPERATOR] = {['('] = 1, ['{'] = 1, [')'] = -1, ['}'] = -1}
-}
-
-return M