postgresql won't install dependencies
This is how I fixed my issue:

`dpkg -l | grep postgres

will show you the postgresql packages that have been installed.  Run:

 sudo apt-get --purge remove 


with each package name, separated by a space, following remove.

root@vps1484:/home# dpkg -l | grep postgres
ii  postgresql                                                  9.3+146really9.1+148             all          object-relational SQL database (supported version)
ii  postgresql-9.1                                              9.1.13-0ubuntu0.13.10            amd64        object-relational SQL database, version 9.1 server
ii  postgresql-client                                           9.3+146really9.1+148             all          front-end programs for PostgreSQL (supported version)
ii  postgresql-client-9.1                                       9.1.13-0ubuntu0.13.10            amd64        front-end programs for PostgreSQL 9.1
ii  postgresql-client-common                                    148                              all          manager for multiple PostgreSQL client versions
ii  postgresql-common                                           148                              all          PostgreSQL database-cluster manager
ii  postgresql-contrib                                          9.3+146really9.1+148             all          additional facilities for PostgreSQL (supported version)
iU  postgresql-contrib-9.1                                      9.1.15-0ubuntu0.12.04            amd64        additional facilities for PostgreSQL
root@vps1484:/home# sudo apt-get --purge remove postgresql postgresql-9.1 postgresql-client postgresql-client-9.1 postgresql-client-comment postgresql-common postgresql-contrib postgresql-contrib-9.1
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package postgresql-client-comment
root@vps1484:/home# sudo apt-get --purge remove postgresql postgresql-9.1 postgresql-client postgresql-client-9.1 postgresql-client-common postgresql
-common postgresql-contrib postgresql-contrib-9.1
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following package was automatically installed and is no longer required:
  libaio1
Use 'apt-get autoremove' to remove it.
The following packages will be REMOVED:
  postgresql* postgresql-9.1* postgresql-client* postgresql-client-9.1* postgresql-client-common* postgresql-common* postgresql-contrib*
  postgresql-contrib-9.1*
0 upgraded, 0 newly installed, 8 to remove and 8 not upgraded.
1 not fully installed or removed.
After this operation, 16.3 MB disk space will be freed.
Do you want to continue [Y/n]? y
(Reading database ... 98720 files and directories currently installed.)
Removing postgresql-contrib ...
Removing postgresql-contrib-9.1 ...
Removing postgresql ...
Removing postgresql-9.1 ...
 * Stopping PostgreSQL 9.1 database server                                                                                                    [ OK ] 
Purging configuration files for postgresql-9.1 ...
Dropping cluster main...
Removing postgresql-client ...
Removing postgresql-client-9.1 ...
update-alternatives: warning: alternative /usr/share/postgresql/9.1/man/man1/psql.1.gz (part of link group psql.1.gz) doesn't exist; removing from list of alternatives
update-alternatives: warning: /etc/alternatives/psql.1.gz is dangling; it will be updated with best choice
Removing postgresql-common ...
 * No PostgreSQL clusters exist; see "man pg_createcluster"
Removing 'diversion of /usr/bin/pg_config to /usr/bin/pg_config.libpq-dev by postgresql-common'
Purging configuration files for postgresql-common ...
dpkg: warning: while removing postgresql-common, directory '/var/lib/postgresql' not empty so not removed
Removing postgresql-client-common ...
Purging configuration files for postgresql-client-common ...
Processing triggers for man-db ...