Replace two cmbtp_* vars with single cmbtp variable

[martinholmer]

This pull request implements the solution suggested by Dan @feenberg to a problem discussed in taxcalc repo issue 1073. The use of the new puf.csv file generated by this taxdata pull request is demonstrated in taxcalc repo pull request 1077.

@MattHJensen @Amy-Xu @andersonfrailey

[andersonfrailey]

@martinholmer looks good to me. I can produce and distribute the new puf.csv when this is merged.

[Amy-Xu]

Great! Thanks Martin! Merging.

[martinholmer]

@andersonfrailey said:

I can produce and distribute the new puf.csv when [#48] is merged.

Now that both #43 and #48 have been merged by @Amy-Xu, do you want to distribute the new puf.csv file? When using the master branch I generate a puf.csv file that looks like this:

$ ls -l puf-2016-11-21.csv
-rw-r--r--  1 mrh  staff  50953138 Nov 21 15:38 puf-2016-11-21.csv

$ ~/work/OSPC/csvvars puf-2016-11-21.csv | head
1 age_head
2 age_spouse
3 DSI
4 EIC
5 FLPDYR
6 f2441
7 f6251
8 MARS
9 MIDR
10 n24

$ ~/work/OSPC/csvvars puf-2016-11-21.csv | tail
72 cmbtp
73 e00200p
74 e00200s
75 e00900p
76 e00900s
77 e02100p
78 e02100s
79 nu13
80 elderly_dependent
81 nu05