add package list for rhel7

doc/rhel7_package_list.txt

+- make
+- autoconf
+- expect
+- gcc
+- g++
+- subversion
+- zlib-devel
+- openssl-devel
+- libffi-devel
+- openldap-devel
+- readline-devel
+- ncurses-devel
+- qt-x11
+- qt-postgresql
+- qt-devel
+- gtk2-devel