Fix invalid makefile sed commands on Linux

Some of the makefile regexes contained one too many backslashes.
On Mac, make/bash (not sure which) seems to ignore the extra backslash,
but on Linux, the extra backslash causes sed to fail to do the proper
replacements.

`sed "s/\\\\\textbar{}/|/g"`
should have been (notice there are four, not five, backslashes)
`sed "s/\\\\textbar{}/|/g"`

You should check each line where I modified backslash count just to make sure we are on the same page.