Enable ShellCheck rules

Enabled ShellCheck rules:
  SC1087
  SC2001
  SC2004
  SC2005
  SC2006
  SC2016
  SC2028
  SC2048
  SC2066 (note that IFS already contains only a line feed)
  SC2116
  SC2166
  SC2181
  SC2206
  SC2207
  SC2230
  SC2236

test/lint/lint-shell.sh

@@ -23,25 +23,9 @@ fi
 
 # Disabled warnings:
 disabled=(
-    SC1087 # Use braces when expanding arrays, e.g. ${array[idx]} (or ${var}[.. to quiet).
-    SC2001 # See if you can use ${variable//search/replace} instead.
-    SC2004 # $/${} is unnecessary on arithmetic variables.
-    SC2005 # Useless echo? Instead of 'echo $(cmd)', just use 'cmd'.
-    SC2006 # Use $(..) instead of legacy `..`.
-    SC2016 # Expressions don't expand in single quotes, use double quotes for that.
-    SC2028 # echo won't expand escape sequences. Consider printf.
     SC2046 # Quote this to prevent word splitting.
-    SC2048 # Use "$@" (with quotes) to prevent whitespace problems.
-    SC2066 # Since you double quoted this, it will not word split, and the loop will only run once.
     SC2086 # Double quote to prevent globbing and word splitting.
-    SC2116 # Useless echo? Instead of 'cmd $(echo foo)', just use 'cmd foo'.
     SC2162 # read without -r will mangle backslashes.
-    SC2166 # Prefer [ p ] {&&,||} [ q ] as [ p -{a,o} q ] is not well defined.
-    SC2181 # Check exit code directly with e.g. 'if mycmd;', not indirectly with $?.
-    SC2206 # Quote to prevent word splitting, or split robustly with mapfile or read -a.
-    SC2207 # Prefer mapfile or read -a to split command output (or quote to avoid splitting).
-    SC2230 # which is non-standard. Use builtin 'command -v' instead.
-    SC2236 # Don't force -n instead of ! -z.
 )
 shellcheck -e "$(IFS=","; echo "${disabled[*]}")" \
     $(git ls-files -- "*.sh" | grep -vE 'src/(secp256k1|univalue)/')