switch to --progress-bar in curl
make sure rvm_is_a_function can be checked also in subcommands
do not do curl --progress-bar when rvm is not a function
Merge pull request #1474 from wayneeseguin/bugfix/curl_hanging_chef-rvm_136_and_157

try to fix curl problems
NEXT: schedule #1747 for 1.18.4
Fixing verify download typo in help files.
Merge pull request #1478 from cwgem/help-typo

Fix --verify-download typo in help files
use java7 for ubuntu / fedora, closes #1460, fix #1466
Merge branch 'master' of github.com:wayneeseguin/rvm
ubunut java7 works starting from 11.10, update #1460