Change command variable assignments to use LC_ALL

LC_ALL and specific locale variables like LC_NUMERIC override LANG, so
if a user sets a locale variable like LC_NUMERIC in their shell, using
LANG as a command variable assignment won't change anything. This causes
the command to output in the users local and could cause parsing errors.

In places where we need the output to be in ANSI C format, set LC_ALL=C
instead of LANG.

On line 1066, both LANG and LC_ALL don't need to be set, since LC_ALL
takes precedence. The change to include both was done in commit
0fb81d5.

Fixes #548

liquidprompt

@@ -196,12 +196,12 @@ case "$LP_OS" in
             # If you have problems with syntax coloring due to the following
             # line, do this: ln -s liquidprompt liquidprompt.bash
             # and edit liquidprompt.bash
-            read bol lp_cpu_load eol <<<"$( LANG=C sysctl -n vm.loadavg )"
+            read bol lp_cpu_load eol <<<"$( LC_ALL=C sysctl -n vm.loadavg )"
         }
         ;;
     SunOS)
         _lp_cpu_load () {
-            read lp_cpu_load <<<"$( LANG=C uptime | sed 's/.*load average: *\([0-9.]*\).*/\1/' )"
+            read lp_cpu_load <<<"$( LC_ALL=C uptime | sed 's/.*load average: *\([0-9.]*\).*/\1/' )"
         }
 esac
 
@@ -593,7 +593,7 @@ _lp_connection()
     else
         # tmux: see GH #304
         # TODO check on *BSD
-        local whoami="$(LANG=C who am i)"
+        local whoami="$(LC_ALL=C who am i)"
         local sess_parent="$(ps -o comm= -p $PPID 2> /dev/null)"
         if [[ x"$whoami" != *'('* || x"$whoami" = *'(:'* || x"$whoami" = *'(tmux'* ]]; then
             echo lcl  # Local
@@ -1066,7 +1066,7 @@ _lp_svn_branch()
 
     local root=
     local url=
-    eval "$(LANG=C LC_ALL=C svn info 2>/dev/null | sed -n 's/^URL: \(.*\)/url="\1"/p;s/^Repository Root: \(.*\)/root="\1"/p' )"
+    eval "$(LC_ALL=C svn info 2>/dev/null | sed -n 's/^URL: \(.*\)/url="\1"/p;s/^Repository Root: \(.*\)/root="\1"/p' )"
     [[ -z "${root-}" ]] && return
 
     # Make url relative to root
@@ -1522,7 +1522,7 @@ if (( LP_ENABLE_TEMP )); then
     {
         local -i i
         # Only the integer part is retained
-        for i in $(LANG=C acpi -t |
+        for i in $(LC_ALL=C acpi -t |
                 sed 's/.* \(-\?[0-9]*\)\.[0-9]* degrees C$/\1/p'); do
             (( $i > ${temperature:-0} )) && temperature=i
         done