Use keywords instead of constants

Marked keywords like "server" or "location" as keyword instead of
constants, fixed namespace. Added constants for SSL, added some
keywords.
remove theme
update strings and variables
update regexps
ssl constants
constant -> punctuation for braces, parens, etc
add sign and units
parse ip as a number
fix double quoted strings
server_name_in_redirect
proxy_cache_*
few cache "functions"
proxy_temp_path
booleans
few support constants
\b isn't enough
try_files
fastcgi_split_path_info
markdown rules github now 6 years later
useless list of scopes